Thiourea group iv transition metal catalysts and polymerization systems

ABSTRACT

Catalyst compositions and polymerization systems include at least one thiourea complex according to Formula (I): MQ a X 4-a  (I) in which M is Ti, Zr, or Hf; a is 1 or 2; each group Q of the thiourea complex is a bidentate thiourea ligand bound to the metal center and having Formula (Ia), Formula (Ib), or Formula (Ic): (Formulas should be inserted here). In Formulas (Ia), (Ib), and (Ic), each group R 1 , R 2 , and R 3  is independently chosen from alkyl groups or aryl groups; each group Z 1  or Z 2  is independently chosen from alkylene groups. If a=2, groups R 1  of the two groups Q are optionally linked, or groups R 3  of the two groups Q are optionally linked. Each X is covalently bonded or coordinated to the metal center and is independently chosen from alkyl groups or halides. The polymerization systems may be configured to copolymerize ethylene and α-olefins.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims priority to U.S. Provisional Patent ApplicationSer. No. 62/402,200 filed Sep. 30, 2016, which is incorporated byreference in its entirety.

BACKGROUND Field

The present specification generally relates to transition-metalcatalysts and, more specifically, to thiourea group IV transition metalcatalysts for polymerization reactions, including the synthesis ofethylene/α-olefin copolymers.

Technical Background

Olefin based polymers are utilized in the manufacture of a variety ofarticles and products, and thus, there is a high industrial demand forsuch polymers. Olefin based polymers, such as polyethylene and/orpolypropylene, are produced via various catalyst systems. Selection ofsuch catalyst systems used in the polymerization process is an importantfactor contributing to the characteristics and properties of such olefinbased polymers.

The polyolefin polymerization process can be varied in a number of waysto produce a wide variety of resultant polyolefin resins havingdifferent physical properties suitable for use in differentapplications. It is generally known that polyolefin can be produced insolution phase polymerization process, gas phase polymerization process,and/or slurry phase polymerization process in one or more reactors, forexample, connected in series or parallel, in the presence of one or morecatalyst systems.

Despite the research efforts in developing catalyst systems suitable forpolyolefin polymerization, such as polyethylene, there is still a needfor improved polymerization catalysts to meet industrial demand forolefin based polymers.

SUMMARY

Accordingly, the present embodiments are directed to catalyst systems,which provide alternative synthetic schemes for meeting industrialdemand of olefin based polymers.

According to some embodiments, compositions or catalytic compositionsinclude at least one thiourea complex according to the Formula (I):

MQ_(a)X_(4-a)  (I)

in which M is Ti, Zr, or Hf; a is 1 or 2; each group X is covalentlybonded or coordinated to the metal center and is independently chosenfrom alkyl groups, halides, or amides; and each group Q of the thioureacomplex is a bidentate thiourea ligand bound to the metal center andindependently chosen from groups having Formula (Ia), Formula (Ib), orFormula (Ic):

In Formulas (Ia), (Ib), and (Ic), each group R¹, R², and R³ isindependently chosen from alkyl groups or aryl groups; and each group Z¹or Z² is independently chosen from alkylene groups. Thus, if a=2, thetwo groups Q of the thiourea complex of Formula (I) may be the same ordifferent. If a=2, groups R¹ of the two groups Q are optionally linkedto each other through at least one covalent bond, or groups R³ of thetwo groups Q are optionally linked to each other through at least onecovalent bond. The polymerization systems may be configured tocopolymerize ethylene and α-olefins.

According to some embodiments, the at least one thiourea complexaccording to the Formula (I) has Formula (IIa), Formula (IIb), orFormula (IIc):

where M, R¹, R², R³, Z¹, Z², and X are as defined in Formula (I). Eachgroup X in complexes of Formula (IIa), Formula (IIb), or Formula (IIc)may be the same or different.

According to some embodiments, the at least one thiourea complexaccording to the Formula (I) has Formula (IIIa), Formula (IIIb), Formula(IIIc), Formula (IIId), Formula (IIIe), or Formula (IIIf):

where M, R¹, R², R³, Z¹, Z², and X are as defined in Formula (I). Thetwo groups R¹ in complexes of Formula (IIIa), Formula (IIId), or Formula(IIIe) may be the same or different. The two groups R² of complexes ofFormula (IIIa) may be the same or different. The two groups R³ incomplexes of Formula (IIIa), Formula (IIIb), Formula (IIIc) may be thesame or different. The two groups Z¹ in complexes of Formula (IIIc) maybe the same or different. The two groups Z² in complexes of Formula(IIIe) may be the same or different. The two groups X in complexes ofany of Formulas (IIIa)-(IIIf) may be the same or different.

According to some embodiments, the at least one thiourea complexaccording to the Formula (I) has Formula (IVa), Formula (IVb), orFormula (IVc):

where M, R², R³, Z², and X are as defined in Formula (I); and Z³ is analkylene group formed from the joining of two groups R¹ as defined inFormula (I) through at least one covalent bond. The two groups R² incomplexes of Formula (IVa) may be the same or different. The two groupsR³ in complexes of Formula (IVa) may be the same or different. The twogroups Z² in complexes of Formula (IVc) may be the same or different.The two groups X in complexes of any of Formulas (IVa)-(IVc) may be thesame or different.

According to some embodiments, the at least one thiourea complexaccording to the Formula (I) has Formula (Va), Formula (Vb), or Formula(Vc):

where M, R¹, R², Z¹, and X are as defined in Formula (I); and Z⁴ is analkylene group formed from the joining of two groups R³ as defined inFormula (I) through at least one covalent bond. The two groups R¹ incomplexes of Formula (Va) may be the same or different. The two groupsR² in complexes of Formula (Va) may be the same or different. The twogroups Z¹ in complexes of Formula (Vc) may be the same or different. Thetwo groups X in complexes of any of Formulas (Va)-(Vc) may be the sameor different.

Further embodiments are directed to polymerization systems configured tocopolymerize ethylene and an α-olefin comonomer in the presence of acatalytic amount of compositions that include at least one thioureacomplex according to at least one embodiment of this disclosure.

Further embodiments are directed to ethylene-co-alkylene copolymersproduced from a polymerization system in which a catalytic amount of acomposition containing at least one thiourea complex according to atleast one embodiment of this disclosure is present during polymerizationof ethylene and an α-olefin.

Further embodiments are directed to polymerization methods includingreacting ethylene and an α-olefin comonomer in the presence of acatalytic amount of a composition containing at least one thioureacomplex according to at least one embodiment of this disclosure to forman ethylene-co-alkylene copolymer. In some embodiments, the α-olefincomonomer may include at least one C₃-C₁₂ α-olefin such as, for example,1-octene.

Additional features and advantages of the embodiments described hereinwill be set forth in the detailed description which follows, and in partwill be readily apparent to those skilled in the art from thatdescription or recognized by practicing the embodiments describedherein, including the detailed description which follows, the claims, aswell as the appended drawings.

It is to be understood that both the foregoing general description andthe following detailed description describe various embodiments and areintended to provide an overview or framework for understanding thenature and character of the claimed subject matter. The accompanyingdrawings are included to provide a further understanding of the variousembodiments, and are incorporated into and constitute a part of thisspecification. The drawings illustrate the various embodiments describedherein, and together with the description serve to explain theprinciples and operations of the claimed subject matter.

DETAILED DESCRIPTION Definitions

Common abbreviations used in this disclosure may include Me: methyl; Et:ethyl; Ph: phenyl; Bn: benzyl (—CH₂-Ph); THF: tetrahydrofuran; Et₂O:diethyl ether; C₆D₆: deuterated benzene; CDCl₃: deuterated chloroform;DMSO-d₆: deuterated dimethylsulfoxide; ZrBn₄: zirconium(IV) tetrabenzyl;HfBn₄: hafnium(IV) tetrabenzyl; N₂: nitrogen gas; MMAO: modifiedmethylaluminoxane; NMR: nuclear magnetic resonance; DSC: differentialscanning calorimetry; mmol: millimoles; mL: milliliters; M: molar; min:minutes; h: hours; d: days; GPC: gel permeation chromatography; M_(w):weight average molecular weight; M_(n): number average molecular weight.

The term “independently selected” is used herein to indicate that the Rgroups, such as, R¹, R², R³, R⁴, and R⁵ can be identical or different(e.g. R¹, R², R³, R⁴, and R⁵ may all be substituted alkyls or R¹ and R²may be a substituted alkyl and R³ may be an aryl, etc.). Use of thesingular includes use of the plural and vice versa (e.g., a hexanesolvent, includes hexanes). A named R group will generally have thestructure that is recognized in the art as corresponding to R groupshaving that name. These definitions are intended to supplement andillustrate, not limit, the definitions known to those of skill in theart.

The terms “moiety,” “functional group,” or “group,” may be usedinterchangeably in this specification, but those of skill in the art mayrecognize certain parts of a complex or compound as being a moietyrather than a functional group and vice versa. Additionally, the term“moiety” includes functional groups and/or discrete bonded residues thatare present in the compounds or metal complexes of this disclosure. Theterm “moiety” as used in the present application is inclusive ofindividual units in the copolymers or the individual units within apolymeric ligand, as described in the general formulas of the presentdisclosure.

The term “complex” means a metal and ligand coordinated together to forma single molecular compound. The coordination may be formed throughdative or covalent bonds. For the purposes of illustration, certainrepresentative groups are defined within this disclosure. Thesedefinitions are intended to supplement and illustrate, not limit, thedefinitions known to those of skill in the art.

The term “aliphatic” encompasses the terms “alkyl,” “branching alkyl,”“(C₁-C₄₀)hydrocarbyls,” “substituted (C₁-C₄₀)hydrocarbyls,”“(C₃-C₄₀)hydrocarbylene,” and “substituted (C₃-C₄₀)hydrocarbylene.”

The term “heteroaliphatic” includes “(C₁-C₄₀)heterohydrocarbyls,” and“substituted (C₁-C₄₀)heterohydrocarbyls,”“[(C+Si)₃-(C+Si)₄₀]organosilylene,” “substituted[(C+Si)₃—(C+Si)₄₀]organosilylene,” “[(C+Ge)₃-(C+Ge)₄₀]organogermylene,”and substituted [(C+Ge)₃-(C+Ge)₄₀]organogermylene.”

The term “aromatic” or “aryl” encompasses the terms: “(C₆-C₄₀)aryl” and“substituted (C₆-C₄₀)aryl group.” The term “heteroaromatic” includes“(C₁-C₄₀)heteroaryl,” and “(C₂-C₄₀)heteroaryl.”

When used to describe certain carbon atom-containing chemical groups(e.g., (C₁-C₄₀)alkyl), the parenthetical expression (C₁-C₄₀) can berepresented by the form “(C_(x)-C_(y)),” which means that theunsubstituted version of the chemical group comprises from a number xcarbon atoms to a number y carbon atoms, wherein each x and yindependently is an integer as described for the chemical group. TheR^(S) substituted version of the chemical group can contain more than ycarbon atoms depending on nature of R^(S). Thus, for example, anunsubstituted (C₁-C₄₀)alkyl contains from 1 to 40 carbon atoms (x=1 andy=40). When the chemical group is substituted by one or more carbonatom-containing R^(S) substituents, the substituted (C_(x)-C_(y))chemical group may comprise more than y total carbon atoms; i.e., thetotal number of carbon atoms of the carbon atom-containingsubstituent(s)-substituted (C_(x)-C_(y)) chemical group is equal to yplus the sum of the number of carbon atoms of each of the carbonatom-containing substituent(s). Any atom of a chemical group that is notspecified herein is understood to be a hydrogen atom.

In some embodiments, each of the chemical groups (e.g. R¹, R², R³) ofthe compounds and metal complex of the general formulas in thisdisclosure may be unsubstituted, that is, can be defined without use ofa substituent R^(S), provided the above-mentioned conditions aresatisfied. In other embodiments, at least one of the chemical groups ofthe compounds and metal complexes of the general formulas of thisdisclosure independently contain one or more of the substituents R^(S).When a compound contains two or more substituents R^(S), each R^(S)independently is bonded to a same or different substituted chemicalgroup. When two or more R^(S) are bonded to a same chemical group, theyindependently are bonded to a same or different carbon atom orheteroatom, as the case may be, in the same chemical group up to andincluding persubstitution of the chemical group.

The term “persubstitution” means each hydrogen atom (H) bonded to acarbon atom or heteroatom of a corresponding unsubstituted compound orfunctional group, as the case may be, is replaced by a substituent(e.g., R^(S)). The term “polysubstitution” means each of at least two,but not all, hydrogen atoms (H) bonded to carbon atoms or heteroatoms ofa corresponding unsubstituted compound or functional group, as the casemay be, is replaced by a substituent (e.g., R^(S)). The term“monosubstitution” means that only one hydrogen atom (H) bonded to acarbon atom or heteroatom of a corresponding unsubstituted compound orfunctional group, as the case may be, is replaced by a substituent(e.g., R^(S)). The (C₁-C₁₈)alkylene and (C₁-C₈)alkylene substituents areespecially useful for forming substituted chemical groups that arebicyclic or tricyclic analogs, as the case may be, of correspondingmonocyclic or bicyclic unsubstituted chemical groups.

As used herein, the definitions of the terms hydrocarbyl,heterohydrocarbyl, hydrocarbylene, heterohydrocarbylene, alkyl,alkylene, heteroalkyl, heteroalkylene, aryl, arylene, heteroaryl,heteroarylene, cycloalkyl, cycloalkylene, heterocycloalkyl,heterocycloalkylene, organosilylene, organogermylene are intended toinclude every possible stereoisomer.

Heteroalkyl and heteroalkylene groups are saturated straight or branchedchain radicals or diradicals, respectively, containing (C₁-C₄₀)carbonatoms, and one or more of the heteroatoms or heteroatomic groups O; S;N; S(O); S(O)₂; S(O)₂N; Si(R^(C))₂; Ge(R^(C))₂; P(R^(C)); P(O)(R^(C));and N(R^(C)), as defined above, wherein each of the heteroalkyl andheteroalkylene groups independently are unsubstituted or substituted byone or more R^(S). Examples of substituted and unsubstituted heteroalkylgroups are methoxyl; ethoxyl; trimethylsilyl; dimethylphenylsilyl;tert-butyldimethylsilyl; and dimethylamino.

As used herein, the term “(C₁-C₄₀)hydrocarbyl” means a hydrocarbonradical of from 1 to 40 carbon atoms and the term“(C₁-C₄₀)hydrocarbylene” means a hydrocarbon diradical of from 1 to 40carbon atoms, wherein each hydrocarbon radical and diradicalindependently is aromatic (6 carbon atoms or more) or non-aromatic,saturated or unsaturated, straight chain or branched chain, cyclic(including mono- and polycyclic, fused and non-fused polycyclic,including bicyclic; 3 carbon atoms or more) or acyclic, or a combinationof two or more thereof; and each hydrocarbon radical and diradicalindependently is the same as or different from another hydrocarbonradical and diradical, respectively, and independently is unsubstitutedor substituted by one or more R^(S).

In some embodiments, (C₁-C₄₀)hydrocarbyl independently is anunsubstituted or substituted (C₁-C₄₀)alkyl, (C₃-C₄₀)cycloalkyl,(C₃-C₂₀)cycloalkyl-(C₁-C₂₀)alkylene, (C₆-C₄₀)aryl, or(C₆-C₂₀)aryl-(C₁-C₂₀)alkylene. In further embodiments, each of theaforementioned (C₁-C₄₀)hydrocarbyl groups independently has a maximum of20 carbon atoms (i.e., (C₁-C₂₀)hydrocarbyl), and in other embodiments, amaximum of 15 carbon atoms.

The term “(C₁-C₄₀)alkyl” means a saturated straight or branchedhydrocarbon radical of from 1 to 40 carbon atoms, that is unsubstitutedor substituted by one or more R^(S). Examples of unsubstituted(C₁-C₄₀)alkyl include unsubstituted (C₁-C₂₀)alkyl; unsubstituted(C₁-C₁₀)alkyl; unsubstituted (C₁-C₅)alkyl; methyl; ethyl; 1-propyl;2-propyl; 2,2-dimethylpropyl, 1-butyl; 2-butyl; 2-methylpropyl;1,1-dimethylethyl; 1-pentyl; 1-hexyl; 2-ethylhexyl, 1-heptyl; 1-nonyl;1-decyl; 2,2,4-trimethylpentyl. Examples of substituted (C₁-C₄₀)alkylinclude substituted (C₁-C₂₀)alkyl; substituted (C₁-C₁₀)alkyl;trifluoromethyl; trimethylsilylmethyl; methoxymethyl;dimethylaminomethyl; trimethylgermylmethyl; phenylmethyl (benzyl);2-phenyl-2,2-methylethyl; 2-(dimethylphenylsilyl)ethyl; anddimethyl(t-butyl)silylmethyl.

The term “(C₆-C₄₀)aryl” means an unsubstituted or substituted (by one ormore R^(S)) mono-, bi- or tricyclic aromatic hydrocarbon radical of from6 to 40 carbon atoms, of which at least from 6 to 14 of the carbon atomsare aromatic ring carbon atoms, and the mono-, bi- or tricyclic radicalcomprises 1, 2 or 3 rings, respectively; wherein one ring is aromaticand the optional second and third rings independently are fused ornon-fused and the second and third rings are each independentlyoptionally aromatic. Examples of unsubstituted (C₆-C₄₀)aryl includeunsubstituted (C₆-C₂₀)aryl; unsubstituted (C₆-C₁₈)aryl; phenyl;biphenyl; ortho-terphenyl; meta-terphenyl; fluorenyl;tetrahydrofluorenyl; indacenyl; hexahydroindacenyl; indenyl;dihydroindenyl; naphthyl; tetrahydronaphthyl; phenanthrenyl andtriptycenyl. Examples of substituted (C₆-C₄₀)aryl include substituted(C₆-C₂₀)aryl; substituted (C₆-C₁)aryl; 2,6-bis[(C₁-C₂₀)alkyl]-phenyl;2-(C₁-C₈)alkyl-phenyl; 2,6-bis(C₁-C₈)alkyl-phenyl;2,4,6-tris(C₁-C₈)alkyl-phenyl; polyfluorophenyl; pentafluorophenyl;2,6-dimethylphenyl, 2,6-diisopropylphenyl; 2,4,6-triisopropylphenyl;2,4,6-trimethylphenyl; 2-methyl-6-trimethylsilylphenyl;2-methyl-4,6-diisopropylphenyl; 4-methoxyphenyl; and4-methoxy-2,6-dimethylphenyl.

The term “(C₃-C₄₀)cycloalkyl” means a saturated cyclic or polycyclic(i.e. fused or unfused) hydrocarbon radical of from 3 to 40 carbon atomsthat is unsubstituted or substituted by one or more R^(S). Othercycloalkyl groups (e.g., (C₃-C₁₂)alkyl)) are defined in an analogousmanner. Examples of unsubstituted (C₃-C₄₀)cycloalkyl includeunsubstituted (C₃-C₂₀)cycloalkyl, unsubstituted (C₃-C₁₀)cycloalkyl;cyclopropyl; cyclobutyl; cyclopentyl; cyclohexyl; cycloheptyl;cyclooctyl; cyclononyl; cyclodecyl; octahydroindenyl;bicyclo[4.4.0]decyl; bicyclo[2.2.1]heptyl; and tricyclo[3.3.1.1]decyl.Examples of substituted (C₃-C₄₀)cycloalkyl include substituted(C₃-C₂₀)cycloalkyl; substituted (C₃-C₁₀)cycloalkyl; 2-methylcyclohexyl;and perfluorocyclohexyl.

Examples of (C₁-C₄₀)hydrocarbylene include unsubstituted or substituted(C₃-C₄₀)hydrocarbylene; (C₆-C₄₀)arylene, (C₃-C₄₀)cycloalkylene, and(C₃-C₄₀)alkylene (e.g., (C₃-C₂₀)alkylene). In some embodiments, thediradicals are on the terminal atoms of the hydrocarbylene as in a1,3-alpha, omega diradical (e.g., —CH₂CH₂CH₂—) or a 1,5-alpha, omegadiradical with internal substitution (e.g., —CH₂CH₂CH(CH₃)CH₂CH₂—). Inother embodiments, the diradicals are on the non-terminal atoms of thehydrocarbylene as in a C₇ 2,6-diradical

or a C₇ 2,6-diradical with internal substitution

The terms [(C+Si)₃-(C+Si)₄₀] organosilylene and [(C+Ge)₃-(C+Ge)₄₀]organogermylene are defined as diradicals in which the two radicalbearing atoms of the diradical unit are spaced apart by one or moreintervening carbon, silicon and/or germanium atoms. Such[(C+Si)₃-(C+Si)₄₀] organosilylene and [(C+Ge)₃-(C+Ge)₄₀] organogermylenegroups can be substituted or unsubstituted. In some embodiments thediradicals are on the terminal atoms of the organosilylene ororganogermylene as in a 1,5-α,ω-diradical (e.g.—CH₂CH₂Si(C₂H₅)₂CH₂CHCH₂— and —CH₂CH₂Ge(C₂H₅)₂CH₂CH₂—). In otherembodiments, the diradicals are on the non-terminal atoms of theorganosilylene or organogermylene as in a substituted (C+Si)₇2,6-diradical

and a substituted (C+Ge)₇ 2,6-diradical

The term “(C₁-C₄₀)alkylene” means a saturated or unsaturated straightchain or branched chain diradical of from 1 to 40 carbon atoms that isunsubstituted or substituted by one or more R^(S). Examples ofunsubstituted (C₁-C₄₀)alkylene include unsubstituted (C₃-C₂₀)alkylene,including unsubstituted 1,3-(C₃-C₁₀)alkylene; 1,4-(C₄-C₁₀)alkylene;—(CH₂)₃—; —(CH₂)₄—; —(CH₂)₅—; —(CH₂)₆—; —(CH₂)₇—; —(CH₂)₈−; and—(CH₂)₄CH(CH₃)—. Examples of substituted (C₁-C₄₀)alkylene includesubstituted (C₃-C₂₀)alkylene; —CF₂CF₂CF₂—; and —(CH₂)₁₄C(CH₃)₂(CH₂)₅—(i.e., a 6,6-dimethyl substituted normal-1,20-eicosylene). As mentionedpreviously, two R^(S) may be taken together to form a (C₁-C₄₀)alkylene.Thus, examples of substituted (C₁-C₄₀)alkylene also include1,2-bis(methylene)cyclopentane; 1,2-bis(methylene)cyclohexane;2,3-bis(methylene)-7,7-dimethyl-bicyclo[2.2.1]heptane; and2,3-bis(methylene)bicyclo[2.2.2]octane.

The term “(C₃-C₄₀)cycloalkylene” means a cyclic diradical (i.e., theradicals are on ring atoms) of from 3 to 40 carbon atoms that isunsubstituted or substituted by one or more R^(S). Examples ofunsubstituted (C₃-C₄₀)cycloalkylene are 1,3-cyclobutylene,1,3-cyclopentylene, and 1,4-cyclohexylene. Examples of substituted(C₃-C₄₀)cycloalkylene are 2-trimethylsilyl-1,4-cyclohexylene and1,2-dimethyl-1,3-cyclohexylene.

The terms “(C₁-C₄₀)heterohydrocarbyl” and “(C₁-C₄₀)heterohydrocarbylene”mean a heterohydrocarbon radical or diradical, respectively, of from 1to 40 carbon atoms, and each heterohydrocarbon independently has one ormore heteroatoms or heteroatomic groups O; S; N; S(O); S(O)₂; S(O)₂N;Si(R^(C))₂; Ge(R^(C))₂; P(R^(C)); P(O)(R^(C)); and N(R^(C)), whereinindependently each R^(C) is hydrogen, unsubstituted (C₁-Cis)hydrocarbylor an unsubstituted (C₁-C₁₈)heterohydrocarbyl, or absent (e.g., absentwhen N comprises —N═). Each (C₁-C₄₀)heterohydrocarbyl and(C₁-C₄₀)heterohydrocarbylene independently is unsubstituted orsubstituted (by one or more R^(S)), aromatic or non-aromatic, saturatedor unsaturated, straight chain or branched chain, cyclic (includingmono- and poly-cyclic, fused and non-fused polycyclic) or acyclic, or acombination of two or more thereof; and each is respectively the same asor different from another.

The (C₁-C₄₀)heterohydrocarbyl independently may be unsubstituted orsubstituted (C₁-C₄₀)heteroalkyl, (C₁-C₄₀)hydrocarbyl-O—,(C₁-C₄₀)hydrocarbyl-S—, (C₁-C₄₀)hydrocarbyl-S(O)—,(C₁-C₄₀)hydrocarbyl-S(O)₂—, (C₁-C₄₀)hydrocarbyl-Si(R^(C))₂—,(C₁-C₄₀)hydrocarbyl-Ge(R^(C))₂—, (C₁-C₄₀)hydrocarbyl-N(R^(C))—,(C₁-C₄₀)hydrocarbyl-P(R^(C))—, (C₂-C₄₀)heterocycloalkyl,(C₂-C₁₉)heterocycloalkyl-(C₁-C₂₀)alkylene,(C₃-C₂₀)cycloalkyl-(C₁-C₁₉)heteroalkylene,(C₂-C₁₉)heterocycloalkyl-(C₁-C₂₀)heteroalkylene, (C₁-C₄₀)heteroaryl,(C₁-C₁₉)heteroaryl-(C₁-C₂₀)alkylene,(C₆-C₂₀)aryl-(C₁-C₁₉)heteroalkylene, or(C₁-C₁₉)heteroaryl-(C₁-C₂₀)heteroalkylene.

The term “(C₁-C₄₀)heteroaryl” means an unsubstituted or substituted (byone or more R^(S)) monocyclic, bicyclic or tricyclic heteroaromatichydrocarbon radical of from 1 to 40 total carbon atoms and from 1 to 6heteroatoms, and the monocyclic, bicyclic or tricyclic radical comprises1, 2 or 3 rings, respectively, wherein one ring is heteroaromatic andthe optional second and third rings independently are fused ornon-fused; and the second or third rings are each independentlyoptionally heteroaromatic. Other heteroaryl groups (e.g.,(C₁-C₁₂)heteroaryl)) are defined in an analogous manner. The monocyclicheteroaromatic hydrocarbon radical is a 5-membered or 6-membered ring.The 5-membered ring has from 1 to 4 carbon atoms and from 4 to 1heteroatoms, respectively, each heteroatom being O, S, N, or P. Examplesof 5-membered ring heteroaromatic hydrocarbon radical are pyrrol-1-yl;pyrrol-2-yl; furan-3-yl; thiophen-2-yl; pyrazol-1-yl; isoxazol-2-yl;isothiazol-5-yl; imidazol-2-yl; oxazol-4-yl; thiazol-2-yl;1,2,4-triazol-1-yl; 1,3,4-oxadiazol-2-yl; 1,3,4-thiadiazol-2-yl;tetrazol-1-yl; tetrazol-2-yl; and tetrazol-5-yl. The 6-membered ring has3 to 5 carbon atoms and 1 to 3 heteroatoms, the heteroatoms being N orP. Examples of 6-membered ring heteroaromatic hydrocarbon radical arepyridine-2-yl; pyrimidin-2-yl; and pyrazin-2-yl. The bicyclicheteroaromatic hydrocarbon radical is a fused 5,6- or 6,6-ring system.Examples of the fused 5,6-ring system bicyclic heteroaromatichydrocarbon radical are indol-1-yl; and benzimidazole-1-yl. Examples ofthe fused 6,6-ring system bicyclic heteroaromatic hydrocarbon radicalare quinolin-2-yl; and isoquinolin-1-yl. The tricyclic heteroaromatichydrocarbon radical is a fused 5,6,5-; 5,6,6-; 6,5,6-; or 6,6,6-ringsystem. An example of the fused 5,6,5-ring system is1,7-dihydropyrrolo[3,2-f]indol-1-yl. An example of the fused 5,6,6-ringsystem is 1H-benzo[f]indol-1-yl. An example of the fused 6,5,6-ringsystem is 9H-carbazol-9-yl. An example of the fused 6,5,6-ring system is9H-carbazol-9-yl. An example of the fused 6,6,6-ring system isacrydin-9-yl.

The (C₂-C₄₀)heteroaryl may include 2,7-disubstituted carbazolyl or3,6-disubstituted carbazolyl, wherein each R^(S) independently isphenyl, methyl, ethyl, isopropyl, or tertiary-butyl,2,7-di(tertiary-butyl)-carbazolyl, 3,6-di(tertiary-butyl)-carbazolyl,2,7-di(tertiary-octyl)-carbazolyl, 3,6-di(tertiary-octyl)-carbazolyl,2,7-diphenylcarbazolyl, 3,6-diphenylcarbazolyl,2,7-bis(2,4,6-trimethylphenyl)-carbazolyl or3,6-bis(2,4,6-trimethylphenyl)-carbazolyl.

Examples of unsubstituted (C₂-C₄₀)heterocycloalkyl are unsubstituted(C₂-C₂₀)heterocycloalkyl, unsubstituted (C₂-C₁₀)heterocycloalkyl,aziridin-1-yl, oxetan-2-yl, tetrahydrofuran-3-yl, pyrrolidin-1-yl,tetrahydrothiophen-S,S-dioxide-2-yl, morpholin-4-yl, 1,4-dioxan-2-yl,hexahydroazepin-4-yl, 3-oxa-cyclooctyl, 5-thio-cyclononyl, and2-aza-cyclodecyl.

The term “halogen atom” means fluorine atom (F), chlorine atom (Cl),bromine atom (Br), or iodine atom (I) radical. The term “halide” meansfluoride (F⁻), chloride (Cl⁻), bromide (Br⁻), or iodide (I⁻) anion.

The term “saturated” means lacking carbon-carbon double bonds,carbon-carbon triple bonds, and (in heteroatom-containing groups)carbon-nitrogen, carbon-phosphorous, and carbon-silicon double bonds.When a saturated chemical group is substituted by one or moresubstituents R^(S), one or more double and/or triple bonds optionallymay or may not be present in substituents R^(S).

The term “unsaturated” means containing one or more carbon-carbon doublebonds, carbon-carbon triple bonds, and (in heteroatom-containing groups)carbon-nitrogen, carbon-phosphorous, carbon-silicon double bonds, orcarbon-nitrogen triple bonds, not including any such double bonds thatmay be present in substituents R^(S), if any, or in (hetero)aromaticrings, if any.

Compositions, Thiourea Complexes, and Catalyst Systems

In view of the foregoing definitions, specific embodiments of thepresent application will now be described. It should be understood thatthe disclosure may be embodied in different forms and should not beconstrued as limited to any specific embodiment set forth. Rather, theembodiments are provided so that this disclosure will be thorough andcomplete and will fully convey the scope of the subject matter to thoseskilled in the art.

Compositions according to embodiments of this disclosure include atleast one thiourea complex according to Formula (I):

MQ_(a)X_(4-a)  (I)

In Formula (I), M is a metal center chosen from Ti, Zr, or Hf. In someembodiments, M is titanium. In other embodiments, M is zirconium. Instill other embodiments, M is hafnium. In some embodiments, M is in aformal oxidation state of +2, +3, or +4. In illustrative embodiments, Mis in a formal oxidation state of +4.

In Formula (I), a is 1 or 2 and represents a number of groups Q presentin the thiourea complex. Thus, the at least one thiourea complex mayhave either one group Q or two groups Q. When two groups Q are present(i.e., when a=2), each group Q may be the same or different. Each groupQ of the at least one thiourea complex is a bidentate thiourea ligandbound to the metal center. The bidentate thiourea ligand may haveFormula (Ia), Formula (Ib), or Formula (Ic), in which wavy bonds denotea coordination of an atom to the metal center M and dotted lines denotedelocalization of electrons across multiple bonds:

In embodiments for which a=1, the group Q may have any one of Formula(Ia), Formula (Ib), or Formula (Ic). In embodiments for which a=2, bothgroups Q may have Formula (Ia), both groups Q may have Formula (Ib),both groups may have Formula (Ic), one group Q may have Formula (Ia)while the other group Q has Formula (Ib) or Formula (Ic), or one group Qmay have Formula (Ib) while the other group Q has Formula (Ic).

In the at least one thiourea complex, each group R¹, R², and R³ isindependently chosen from alkyl groups or aryl groups. Thus, if a=2 andtwo groups Q are present, each group R¹, R², and R³ in the at least onethiourea complex may be the same or different from other groups R¹, R²,and R³ in the at least one thiourea complex. Each group Z¹ in the atleast one thiourea complex is independently chosen from alkylene groups.Likewise, if a=2 and two groups Q are present, both having Formula (Ib),for example, each group Z¹, in the at least one thiourea complex may bethe same or different from other groups Z¹ in the at least one thioureacomplex. Each group Z² in the at least one thiourea complex isindependently chosen from alkylene groups. Likewise, if a=2 and twogroups Q are present, both having Formula (Ic), for example, each groupZ², in the at least one thiourea complex may be the same or differentfrom other groups Z² in the at least one thiourea complex.

In Formula (I), if a=2, groups R¹ of the two groups Q, when two groupsR¹ are present, are optionally linked to each other through at least onecovalent bond. In embodiments for which the at least one thioureacomplex according to Formula (I) has a=2 and for which the groups R¹ ofthe two groups Q are linked to each other through at least one covalentbond, the two groups Q of the complex form a single tetradentate ligandbound to the metal center M.

In Formula (I), if a=2, groups R³ of the two groups Q, when two groupsR³ are present, are optionally linked to each other through at least onecovalent bond. In embodiments for which the at least one thioureacomplex according to Formula (I) has a=2 and for which the groups R³ ofthe two groups Q are linked to each other through at least one covalentbond, the two groups Q of the complex form a single tetradentate ligandbound to the metal center M.

In Formula (I), each X is covalently bonded or coordinated to the metalcenter and is independently chosen from alkyl groups or halides.According to embodiments, each X of the at least one thiourea complexaccording to Formula (I) independently is a monodentate or polydentateligand that is neutral, monoanionic, or dianionic. Generally, X and a ofthe at least one thiourea complex of Formula (I) are chosen in such away that the thiourea complexes according to Formula (I) are overallneutral. In some embodiments, each X independently is a monodentateligand. In one embodiment when there are two or more X monodentateligands, each X is the same. In some embodiments the monodentate ligandis the monoanionic ligand. The monoanionic ligand has a net formaloxidation state of −1. Each monoanionic ligand may independently behydride, (C₁-C₄₀)hydrocarbyl carbanion, (C₁-C₄₀)heterohydrocarbylcarbanion, halide, nitrate, carbonate, phosphate, borate, borohydride,sulfate, HC(O)O—, alkoxide or aryloxide (RO—),(C₁-C₄₀)hydrocarbylC(O)O—, HC(O)N(H)—,(C₁-C₄₀)hydrocarbyl-C(O)N((C₁-C₂₀)hydrocarbyl)-,(C₁-C₄₀)hydrocarbyl-C(O)N(H)—, R^(K)R^(L)B—, R^(K)R^(L)N—, R^(K)O—,R^(K)S—, R^(K)R^(L)P—, or R^(M)R^(K)R^(L)Si—, wherein each R^(K), R^(L),and R^(M) independently is hydrogen, (C₁-C₄₀)hydrocarbyl, or(C₁-C₄₀)heterohydrocarbyl, or R^(K) and R^(L) are taken together to forma (C₂-C₄₀)hydrocarbylene or (C₁-C₄₀)heterohydrocarbylene and R^(M) asdefined previously.

In some embodiments at least one monodentate ligand of X independentlyis the neutral ligand. In one embodiment, the neutral ligand is aneutral Lewis base group that is R^(X)NR^(K)R^(L), R^(K)OR^(L),R^(K)SR^(L), or R^(X)PR^(K)R^(L), wherein each R^(X) independently ishydrogen, (C₁-C₄₀)hydrocarbyl, [(C₁-C₁₀)hydrocarbyl]₃Si,[(C₁-C₁₀)hydrocarbyl]₃Si(C₁-C₁₀)hydrocarbyl, or(C₁-C₄₀)heterohydrocarbyl and each R^(K) and R^(L) independently is asdefined previously.

In some embodiments, each X is a monodentate ligand that independentlyis a halogen atom, unsubstituted (C₁-C₂₀)hydrocarbyl, unsubstituted(C₁-C₂₀)hydrocarbylC(O)O—, or an amide such as R^(K)R^(L)N— wherein eachof R^(K) and R^(L) independently is an unsubstituted(C₁-C₂₀)hydrocarbyl. In some embodiments each monodentate ligand X is achlorine atom, (C₁-C₁₀) hydrocarbyl (e.g., (C₁-C₆)alkyl or benzyl),unsubstituted (C₁-C₁₀)hydrocarbylC(O)O—, or R^(K)R^(L)N— wherein each ofR^(K) and R^(L) independently is an unsubstituted (C₁-C₁₀)hydrocarbyl.

In some embodiments there are at least two Xs and the two Xs are takentogether to form a bidentate ligand. In some embodiments the bidentateligand is a neutral bidentate ligand. In one embodiment, the neutralbidentate ligand is a diene of formula(R^(D))₂C═C(R^(D))—C(R^(D))═C(R^(D))₂, wherein each R^(D) independentlyis H, unsubstituted (C₁-C₆)alkyl, phenyl, or naphthyl. In someembodiments the bidentate ligand is a monoanionic-mono(Lewis base)ligand. The monoanionic-mono(Lewis base) ligand may be a 1,3-dionate offormula (D): R^(E)—C(O—)═CH—C(═O)—R^(E) (D), wherein each R^(D)independently is H, unsubstituted (C₁-C₆)alkyl, phenyl, or naphthyl. Insome embodiments the bidentate ligand is a dianionic ligand. Thedianionic ligand has a net formal oxidation state of −2. In oneembodiment, each dianionic ligand independently is carbonate, oxalate(i.e., —O₂CC(O)O—), (C₂-C₄₀)hydrocarbylene dicarbanion, (C₁-C₄₀)heterohydrocarbylene dicarbanion, phosphate, or sulfate.

As previously mentioned, the number and charge (neutral, monoanionic,dianionic) of X are selected depending on the formal oxidation state ofM such that the polymerization catalysts of Formula (I) and overallneutral.

In some embodiments each X is the same, wherein each X is methyl;isobutyl; neopentyl; neophyl; trimethylsilylmethyl; phenyl; benzyl; orchloro. In some embodiments, a is 1 and all groups X are identical. Insome embodiments, a is 2 and all groups X are identical. In someembodiments, all groups X are benzyl. In some embodiments, all groups Xare chloro.

In some embodiments at least two X are different. In some embodiments,each X is a different one of methyl; isobutyl; neopentyl; neophyl;trimethylsilylmethyl; phenyl; benzyl; and chloro.

Further non-limiting embodiments of the at least one thiourea complexhaving Formula (I) will now be described.

Each group R¹ of the at least one thiourea complex according to Formula(I) and having one or two groups Q according to Formula (Ia) or (Ic) isbound to a metal-bound nitrogen atom of the thiourea ligand and isindependently chosen from alkyl groups or aryl groups. Thus, if multiplegroups R¹ are present in one thiourea complex, each individual group R¹may be an alkyl group, each individual group R¹ may be an aryl group, orone or more individual group R¹ may be an alkyl group while one or moreother individual groups R¹ may be an aryl group. In some embodiments,one or more individual groups R¹ may be an alkyl group chosen from(C₁-C₄₀)hydrocarbyls; substituted (C₁-C₄₀)hydrocarbyls;(C₁-C₄₀)heterohydrocarbyls; substituted (C₁-C₄₀)heterohydrocarbyls;(C₁-C₁₀)hydrocarbyls; substituted (C₁-C₁₀)hydrocarbyls;(C₁-C₁₀)heterohydrocarbyls; or substituted (C₁-C₁₀)heterohydrocarbyls,for example. In some embodiments, one or more individual groups R¹ maybe an aryl group chosen from (C₆-C₄₀)aryl groups, substituted (C₆-C₄₀)aryl groups; (C₆-C₁₀)aryl groups, substituted (C₆-C₁₀) aryl groups, forexample.

In illustrative embodiments, each group R¹ may be independently chosenfrom phenyl, substituted phenyl, a (C₃-C₁₀)cycloalkyl group, or a(C₁-C₁₀)alkyl group. In further illustrative embodiments, each group R¹may be independently chosen from phenyl, substituted phenyl, or a(C₃-C₁₀)cycloalkyl group such as cyclohexyl, for example. In furtherillustrative embodiments, each group R¹ may be substituted phenyl. Infurther illustrative embodiments, each group R¹ may be cyclohexyl.

In further illustrative embodiments, one or more group R¹ may beindependently chosen from a (C₃-C₁₀)cycloalkyl group or substitutedphenyl groups according to the following formula:

in which A¹ and A² are independently hydrogen or a (C₁-C₁₀) alkyl group.In some embodiments, groups A¹ and A² may be independently hydrogen;methyl; ethyl; propyl; 1-methylethyl; 1,1-dimethylethyl; or butyl. Inother embodiments, groups A¹ and A² may both be hydrogen, whereby groupR¹ would be phenyl. In other embodiments, groups A¹ and A² may both bemethyl. In other embodiments, groups A¹ and A² may both be1-methylethyl.

Each group R² of the at least one thiourea complex according to Formula(I) and having one or two groups Q according to Formula (Ia) is bound toa secondary nitrogen atom of the thiourea ligand and is independentlychosen from alkyl groups or aryl groups. Thus, if multiple groups R² arepresent in one thiourea complex, each individual group R² may be analkyl group, each individual group R² may be an aryl group, or one ormore individual group R² may be an alkyl group while one or more otherindividual groups R² may be an aryl group. In some embodiments, one ormore individual groups R² may be an alkyl group chosen from(C₁-C₄₀)hydrocarbyls; substituted (C₁-C₄₀)hydrocarbyls;(C₁-C₄₀)heterohydrocarbyls; substituted (C₁-C₄₀)heterohydrocarbyls;(C₁-C₁₀)hydrocarbyls; substituted (C₁-C₁₀)hydrocarbyls;(C₁-C₁₀)heterohydrocarbyls; or substituted (C₁-C₁₀)heterohydrocarbyls,for example. In some embodiments, one or more individual groups R² maybe an aryl group chosen from (C₆-C₄₀)aryl groups, substituted(C₆-C₄₀)aryl groups; (C₆-C₁₀)aryl groups, or substituted (C₆-C₁₀) arylgroups, for example.

In illustrative embodiments, each group R² may be independently chosenfrom (C₁-C₄₀)alkyl groups, (C₁-C₂₀)alkyl groups, (C₁-C₁₀)alkyl groups,or phenyl-terminated (C₁-C₅) hydrocarbyl groups. In further illustrativeembodiments, each group R² may be independently chosen from —(CH₂)_(n)Phgroups, where n is from 0 to 5, from 1 to 5, or from 4 to 5, forexample. In further illustrative embodiments, group R² may be a benzylgroup (—CH₂Ph).

Each group R³ of the at least one thiourea complex according to Formula(I) and having one or two groups Q according to Formula (Ia) or (Ib) isbound to a secondary nitrogen atom of the thiourea ligand and isindependently chosen from alkyl groups or aryl groups. Thus, if multiplegroups R³ are present in one thiourea complex, each individual group R³may be an alkyl group, each individual group R³ may be an aryl group, orone or more individual group R³ may be an alkyl group while one or moreother individual groups R³ may be an aryl group. In some embodiments,one or more individual groups R³ may be an alkyl group chosen from(C₁-C₄₀)hydrocarbyls; substituted (C₁-C₄₀)hydrocarbyls;(C₁-C₄₀)heterohydrocarbyls; substituted (C₁-C₄₀)heterohydrocarbyls;(C₁-C₁₀)hydrocarbyls; substituted (C₁-C₁₀)hydrocarbyls;(C₁-C₁₀)heterohydrocarbyls; or substituted (C₁-C₁₀)heterohydrocarbyls,for example. In some embodiments, one or more individual groups R³ maybe an aryl group chosen from (C₆-C₄₀)aryl groups, substituted (C₆-C₄₀)aryl groups; (C₆-C₁₀)aryl groups, substituted (C₆-C₁₀) aryl groups, forexample.

In illustrative embodiments, each group R³ may be independently chosenfrom (C₁-C₄₀)alkyl groups, (C₁-C₂₀)alkyl groups, (C₁-C₁₀)alkyl groups,or phenyl-terminated (C₁-C₅) hydrocarbyl groups. In further illustrativeembodiments, each group R³ may be independently chosen from —(CH₂)_(n)Phgroups, where n is from 0 to 5, from 1 to 5, or from 4 to 5, forexample. In further illustrative embodiments, group R³ may be a benzylgroup (—CH₂Ph). In further illustrative embodiments, when both R² and R³are present in the at least one thiourea complex and not joined to forma group Z², R³ may be identical to R².

Each group Z¹ of the at least one thiourea complex according to Formula(I) and having one or two groups Q according to Formula (Ia) isindependently chosen from alkylene groups such as, for example,(C₃-C₄₀)hydrocarbylene, substituted (C₃-C₄₀)hydrocarbylene,(C₃-C₁₀)hydrocarbylene, substituted (C₃-C₁₀)hydrocarbylene,[(C+Si)₃-(C+Si)₄₀]organosilylene, substituted[(C+Si)₃-(C+Si)₄₀]organosilylene, [(C+Ge)₃-(C+Ge)₄₀]organogermylene, orsubstituted [(C+Ge)₃-(C+Ge)₄₀]organogermylene. In illustrativeembodiments, each group Z¹ may be a C₄ hydrocarbylene such as —(CH₂)₄—or a C₅ hydrocarbylene such as —(CH₂)₅—.

Each group Z² of the at least one thiourea complex according to Formula(I) and having one or two groups Q according to Formula (Ic) isindependently chosen from alkylene groups such as, for example,(C₃-C₄₀)hydrocarbylene, substituted (C₃-C₄₀)hydrocarbylene,(C₃-C₁₀)hydrocarbylene, substituted (C₃-C₁₀)hydrocarbylene,[(C+Si)₃-(C+Si)₄₀]organosilylene, substituted[(C+Si)₃-(C+Si)₄₀]organosilylene, [(C+Ge)₃-(C+Ge)₄₀]organogermylene, orsubstituted [(C+Ge)₃-(C+Ge)₄₀]organogermylene. In illustrativeembodiments, each group Z² may be a C₄ hydrocarbylene such as —(CH₂)₄—or a C₅ hydrocarbylene such as —(CH₂)₅—.

As previously described, in the at least one thiourea complex accordingto Formula (I), if a=2, groups R¹ of the two groups Q are optionallylinked to each other through at least one covalent bond. In embodimentsfor which the at least one thiourea complex according to Formula (I) hasa=2 and for which the groups R¹ of the two groups Q are linked to eachother through at least one covalent bond, the groups R¹ may form abridging group Z³. When present, bridging groups Z³ of the at least onethiourea complex according to Formula (I) may be independently chosenfrom alkylene groups such as, for example, (C₃-C₄₀)hydrocarbylene,substituted (C₃-C₄₀)hydrocarbylene, (C₃-C₁₀)hydrocarbylene, substituted(C₃-C₁₀)hydrocarbylene, (C₄-C₅)hydrocarbylene, substituted(C₄-C₅)hydrocarbylene, [(C+Si)₃-(C+Si)₄₀]organosilylene, substituted[(C+Si)₃-(C+Si)₄₀]organosilylene, [(C+Ge)₃-(C+Ge)₄₀]organogermylene, orsubstituted [(C+Ge)₃-(C+Ge)₄₀]organogermylene. Bridging groups Z³ willbe described subsequently in greater detail, with reference to thioureacomplexes of Formulas (IVa), (IVb), and (IVc).

As previously described, in the at least one thiourea complex accordingto Formula (I), if a=2, groups R³ of the two groups Q are optionallylinked to each other through at least one covalent bond. In embodimentsfor which the at least one thiourea complex according to Formula (I) hasa=2 and for which the groups R³ of the two groups Q are linked to eachother through at least one covalent bond, the groups R³ may form abridging group Z⁴. When present, bridging groups Z⁴ of the at least onethiourea complex according to Formula (I) may be independently chosenfrom alkylene groups such as, for example, (C₃-C₄₀)hydrocarbylene,substituted (C₃-C₄₀)hydrocarbylene, (C₃-C₁₀)hydrocarbylene, substituted(C₃-C₁₀)hydrocarbylene, (C₄-C₅)hydrocarbylene, substituted(C₄-C₅)hydrocarbylene, [(C+Si)₃-(C+Si)₄₀]organosilylene, substituted[(C+Si)₃-(C+Si)₄₀]organosilylene, [(C+Ge)₃-(C+Ge)₄₀]organogermylene, orsubstituted [(C+Ge)₃-(C+Ge)₄₀]organogermylene. Bridging groups Z⁴ willbe described subsequently in greater detail, with reference to thioureacomplexes of Formulas (Va), (Vb), and (Vc).

Illustrative embodiments of the at least one thiourea complex havingFormula (I) will now be described.

According to some embodiments, the at least one thiourea complex mayhave Formula (I), in which a is 1, such that the at least one thioureacomplex has Formula (IIa), Formula (IIb), or Formula (IIc):

where M, R¹, R², R³, Z¹, Z², and X are as defined in Formula (I) andpreviously described.

In illustrative embodiments, the at least one thiourea complex hasFormula (IIa) or Formula (IIc), and group R¹ is a substituted phenylgroup or a (C₁-C₁₀)cycloalkyl group. Examples of R¹ as substitutedphenyl group include groups according to the following formula:

in which A¹ and A² are independently hydrogen or a (C₁-C₁₀) alkyl group.In some such embodiments, groups A¹ and A² may be independently chosenfrom hydrogen; methyl; ethyl; propyl; 1-methylethyl (isopropyl);1,1-dimethylethyl (tert-butyl); or n-butyl. In other such embodiments,groups A¹ and A² may both be hydrogen, whereby group R¹ is phenyl. Insome embodiments, groups A¹ and A² may be identical. For example, bothgroups A¹ and A² may be methyl; both groups A¹ and A² may be ethyl; bothgroups A¹ and A² may be propyl; both 1-methylethyl; both groups A¹ andA² may be 1,1-dimethylethyl; or both groups A¹ and A² may be butyl. Inother such embodiments, both groups A¹ and A² may be methyl or bothgroups A¹ and A² may be 1-methylethyl.

In illustrative embodiments, the at least one thiourea complex hasFormula (IIa), where R² and R³ are independently —(CH₂)_(n)Ph groups,where n is from 0 to 5, from 1 to 5, or from 4 to 5. In someembodiments, the at least one thiourea complex may have Formula (IIa),where R² and R³ are both —CH₂Ph.

In illustrative embodiments, the at least one thiourea complex hasFormula (IIc), where Z² is a (C₄-C₁₁)alkylene group or a (C₄-C₅)alkylenegroup. In such embodiments, Z² may be a hydrocarbyl group —(CH₂)_(n)—,where n is from 4 to 10 or from 4 to 5. When group Z² is —(CH₂)₄—, thecombination of group Z² and the nitrogen atom to which Z² is bound forma five-membered pyrrolidinyl group. When group Z² is —(CH₂)₅—, thecombination of group Z² and the nitrogen atom to which Z² is bound forma six-membered piperidinyl group.

In illustrative embodiments, the at least one thiourea complex hasFormula (IIc), where Z² is —(CH₂)₄— or —(CH₂)₅—; and each R¹ is adisubstituted phenyl group or a (C₁-C₁₀)cycloalkyl group such ascyclohexyl, for example. Examples of disubstituted phenyl groups include2,5-dimethylphenyl and 2,5-di(1-methylethyl)phenyl.

In illustrative embodiments, the at least one thiourea complex hasFormula (IIa), Formula (IIb), or Formula (IIc) and all groups X areidentical. For example, each group X may be benzyl or each group X maybe chloride.

Specific illustrative and non-limiting embodiments of thiourea complexeshaving Formula (IIa) include compounds C8 and C12:

Specific illustrative and non-limiting embodiments of thiourea complexeshaving Formula (IIc) include compounds C5, C6, C7, C9, C10, and C11:

According to some embodiments, the at least one thiourea complex mayhave Formula (I), in which a is 2, and the at least one thiourea complexmay have Formula (IIIa), Formula (IIIb), Formula (IIIc), Formula (IIId),Formula (IIIe), or Formula (IIIf):

where M, R¹, R², R³, Z¹, Z², and X are as defined in Formula (I) andpreviously described.

In illustrative embodiments, the at least one thiourea complex hasFormula (IIId), Formula (IIIe), or Formula (IIIf), where Z² is a(C₄-C₁₀)alkylene group and groups M, R¹, R², R³, Z¹, and X are asdefined in Formula (I). Examples of such embodiments include those inwhich Z² is a (C₄-C₁₀)hydrocarbyl group, a (C₄-C₅)alkylene group, or a(C₄-C₅)hydrocarbyl group. Further examples of such embodiments includethose in which Z² is —(CH₂)_(n)—, where n is from 4 to 10 or from 4 to5. In particular examples, Z² may be —(CH₂)₄— or —(CH₂)₅—.

In further illustrative embodiments, the at least one thiourea complexhas Formula (IIId), Formula (IIIle), or Formula (IIIf); group Z² may bea (C₄-C₁₀)alkylene group, a (C₄-C₁₀)hydrocarbyl group, a (C₄-C₅)alkylenegroup, or a (C₄-C₅)hydrocarbyl group; one or both groups R¹ may beindependently chosen from cyclohexyl and disubstituted phenyl; andgroups M, R², R³, Z¹, and X are as defined in Formula (I). Examples ofdisubstituted phenyl groups R¹ include those according to the followingformula:

in which A¹ and A² are independently hydrogen or a (C₁-C₁₀) alkyl group.In some such embodiments, groups A¹ and A² may be independently chosenfrom hydrogen; methyl; ethyl; propyl; 1-methylethyl (isopropyl);1,1-dimethylethyl (tert-butyl); or n-butyl. In other such embodiments,groups A¹ and A² may both be hydrogen, whereby group R¹ is phenyl. Insome embodiments, groups A¹ and A² may be identical. For example, groupsA¹ and A² may be both methyl; both ethyl; both propyl; both1-methylethyl; both 1,1-dimethylethyl; or both butyl. In other suchembodiments, both groups A¹ and A² may be methyl or both groups A¹ andA² may be 1-methylethyl.

In illustrative embodiments, the at least one thiourea composition hasFormula (IIIa), Formula (IIIb), Formula (IIIc), Formula (IIId), Formula(IIIe), or Formula (IIIf), in which each X is independently a benzylgroup or a chloride coordinated to the metal center and groups M, R¹,R², R³, Z¹, and Z² are as defined in Formula (I). In illustrativeembodiments, the at least one thiourea composition has Formula (IIIa),Formula (IIIb), Formula (IIIc), Formula (IIId), Formula (IIIe), orFormula (IIIf), in which each X is a benzyl group coordinated to themetal center. In illustrative embodiments, the at least one thioureacomposition has Formula (IIIa), Formula (IIIb), Formula (IIIc), Formula(IIId), Formula (IIIe), or Formula (IIIf), in which each X is a chloridecoordinated to the metal center.

In illustrative embodiments, the at least one thiourea composition hasFormula (IIIa) in which both groups R¹ are identical, both groups R² areidentical, both groups R³ are identical, and both groups X areidentical. Such embodiments represent examples of thiourea complexes ofFormula (I), in which both groups Q are identical. In furtherillustrative embodiments, the at least one thiourea composition hasFormula (IIIc) in which both groups Z¹ are identical, both groups R³ areidentical, and both groups X are identical. Such embodiments alsorepresent additional examples of thiourea complexes of Formula (I), inwhich both groups Q are identical. In further illustrative embodiments,the at least one thiourea composition has Formula (IIIe) in which bothgroups R¹ are identical, both groups Z² are identical, and both groups Xare identical. Such embodiments also represent additional examples ofthiourea complexes of Formula (I), in which both groups Q are identical.When both groups Q of thiourea complexes of Formula (I) are identical,the thiourea complex typically has at least one plane of symmetry.

Specific illustrative and non-limiting embodiments of thiourea complexeshaving Formula (IIIe) include compounds C1, C2, C3, and C4:

According to some embodiments, the at least one thiourea complex mayhave Formula (I), in which a is 2; groups R¹ of the two groups Q arelinked to each other as a bridging group Z³; and the at least onethiourea complex has Formula (IVa), Formula (IVb), or Formula (IVc):

where M, R¹, R², R³, Z², and X are as defined in Formula (I) andpreviously described; and Z³ is an alkylene group formed from thejoining of two groups R¹ as defined in Formula (I) through at least onecovalent bond.

In illustrative embodiments, group Z³ of thiourea complexes according toFormula (IVa), Formula (IVb), or Formula (IVc) may be alkylene groupssuch as, for example, (C₃-C₄₀)hydrocarbylene, substituted(C₃-C₄₀)hydrocarbylene, (C₃-C₁₀)hydrocarbylene, substituted(C₃-C₁₀)hydrocarbylene, [(C+Si)₃-(C+Si)₄₀]organosilylene, substituted[(C+Si)₃-(C+Si)₄₀]organosilylene, [(C+Ge)₃-(C+Ge)₄₀]organogermylene, orsubstituted [(C+Ge)₃-(C+Ge)₄₀]organogermylene. In such embodiments, M,R², R³, Z², and X, as applicable to the particular formula, are asdefined in Formula (I) as previously described. In illustrativeembodiments, group Z³ may be a (C₃-C₁₂)hydrocarbylene, a(C₃-C₁₀)hydrocarbylene, a C₄ hydrocarbylene such as —(CH₂)₄—, or a C₅hydrocarbylene such as —(CH₂)₅—.

In illustrative embodiments, the at least one thiourea composition hasFormula (IVa), Formula (IVb), or Formula (IVc), in which each X isindependently a benzyl group or a chloride coordinated to the metalcenter. In illustrative embodiments, the at least one thioureacomposition has Formula (IVa), Formula (IVb), or Formula (IVc), in whicheach X is a benzyl group coordinated to the metal center. Inillustrative embodiments, the at least one thiourea composition hasFormula (IVa), Formula (IVb), or Formula (IVc), in which each X is achloride coordinated to the metal center.

In illustrative embodiments, the at least one thiourea composition hasFormula (IVa) in which both groups R² are identical, both groups R³ areidentical, and both groups X are identical. Such embodiments representexamples of thiourea complexes of Formula (I), in which both groups Qare identical. In further illustrative embodiments, the at least onethiourea composition has Formula (IVc) in which both groups Z² areidentical and both groups X are identical. Such embodiments representadditional examples of thiourea complexes of Formula (I), in which bothgroups Q are identical.

According to some embodiments, the at least one thiourea complex mayhave Formula (I), in which a is 2; groups R³ of the two groups Q arelinked to each other as a bridging group Z⁴; and the at least onethiourea complex has Formula (Va), Formula (Vb), or Formula (Vc):

where M, R¹, R², Z¹, and X are as defined in Formula (I) and previouslydescribed; and Z⁴ is an alkylene group formed from the joining of twogroups R³ as defined in Formula (I) through at least one covalent bond.

In illustrative embodiments, group Z⁴ of thiourea complexes according toFormula (Va), Formula (Vb), or Formula (Vc) may be alkylene groups suchas, for example, (C₃-C₄₀)hydrocarbylene, substituted(C₃-C₄₀)hydrocarbylene, (C₃-C₁₀)hydrocarbylene, substituted(C₃-C₁₀)hydrocarbylene, [(C+Si)₃-(C+Si)₄₀]organosilylene, substituted[(C+Si)₃-(C+Si)₄₀]organosilylene, [(C+Ge)₃-(C+Ge)₄₀]organogermylene, orsubstituted [(C+Ge)₃-(C+Ge)₄₀]organogermylene. In such embodiments, M,R¹, R², Z¹, and X, as applicable to the particular formula, are asdefined in Formula (I) as previously described. In illustrativeembodiments, group Z⁴ may be a (C₃-C₁₂)hydrocarbylene, a(C₃-C₁₀)hydrocarbylene, a C₄ hydrocarbylene such as —(CH₂)₄—, or a C₅hydrocarbylene such as —(CH₂)₅—.

In illustrative embodiments, the at least one thiourea composition hasFormula (Va), Formula (Vb), or Formula (Vc), in which each X isindependently a benzyl group or a chloride coordinated to the metalcenter. In illustrative embodiments, the at least one thioureacomposition has Formula (Va), Formula (Vb), or Formula (Vc), in whicheach X is a benzyl group coordinated to the metal center. Inillustrative embodiments, the at least one thiourea composition hasFormula (Va), Formula (Vb), or Formula (Vc), in which each X is achloride coordinated to the metal center.

In illustrative embodiments, the at least one thiourea composition hasFormula (Va) in which both groups R¹ are identical, both groups R² areidentical, and both groups X are identical. Such embodiments representexamples of thiourea complexes of Formula (I), in which both groups Qare identical. In further illustrative embodiments, the at least onethiourea composition has Formula (Vc) in which both groups Z¹ areidentical and both groups X are identical. Such embodiments representadditional examples of thiourea complexes of Formula (I), in which bothgroups Q are identical.

In further embodiments, the compositions may include combinations ormixtures of a plurality of thiourea complexes according to Formula (I).For example, the compositions may include two, three, four, five, ormore than five thiourea complexes according to Formula (I). Inillustrative embodiments, the plurality of thiourea complexes accordingto Formula (I) may include any of the compounds C1, C2, C3, C4, C5, C6,C7, C8, C9, C10, C11, or C12, as previously described, in anycombination or proportion.

Polyolefin Compositions

Polyolefin compositions such as ethylene-co-alkylene copolymersaccording to embodiments of this disclosure include the reaction productof ethylene and one or more olefinic monomers in the presence of acatalytic amount of at least one of the compositions previouslydescribed, which include at least one thiourea complex, underpolymerization conditions and optionally in the presence of one or moreco-catalysts and/or scavengers.

The polyolefin compositions can be, for example, be an ethylene-basedpolymer, for example homopolymers and/or interpolymers (includingcopolymers) of ethylene and optionally one or more comonomers such asα-olefins. Such ethylene-based polymers can have a density in the rangeof 0.860 g/cm³ to 0.973 g/cm³. All individual values and subranges from0.860 g/cm³ to 0.973 g/cm³ are included herein and disclosed herein; forexample, the density can be from a lower limit of 0.860, 0.880, 0.885,0.900, 0.905, 0.910, 0.915, or 0.920 g/cm³ to an upper limit of 0.973,0.963, 0.960, 0.955, 0.950, 0.925, 0.920, 0.915, 0.910, or 0.905 g/cm³.

As used herein, the term “ethylene-based polymer” means a polymer havinggreater than 50 mol. % units derived from ethylene monomer.

In one embodiment, the ethylene-based polymers can have a long chainbranching frequency in the range of from 0.0 to 3 long chain branches(LCB) per 1000 carbon atoms. In one embodiment, the ethylene-basedpolymers can have a molecular weight distribution (M_(w)/M_(n), alsoknown as polydispersity index (PDI)) (measured according to theconventional GPC method) in the range of from greater than or equal to2.0. All individual values and subranges from greater than or equal to 2are included herein and disclosed herein; for example, theethylene/α-olefin copolymer may have a molecular weight distribution(M_(w)/M_(n)) in the range of from 2 to 20; or in the alternative, theethylene/α-olefin interpolymer may have a molecular weight distribution(M_(w)/M_(n)) in the range of from 2 to 5.

In another embodiment, the ethylene-based polymers may have molecularweight distribution, M_(w)/M_(n), of less than 2, e.g., when chaintransfer agents are used in the polymerization. All individual valuesand subranges less than 2 are included and disclosed herein. Forexample, the M_(w)/M_(n) of the ethylene-based polymers may be less than2, or in the alternative, less than 1.9, or in the alternative, lessthan 1.8, or in the alternative, less than 1.5. In a particularembodiment, the ethylene-based polymer has a molecular weightdistribution from 0.5 to 2.

In one embodiment, the ethylene-based polymers can have a molecularweight (M_(w)) in the range of from equal to or greater than 20,000g/mole, for example, in the range of from 20,000 to 1,000,000 g/mole, orin the alternative, from 20,000 to 350,000 g/mole, or in thealternative, from 100,000 to 750,000 g/mole.

In one embodiment, the ethylene-based polymers can have a melt index(I₂) in the range of 0.02 to 200 g/10 minutes. All individual values andsubranges from 0.02 to 200 g/10 minutes are included herein anddisclosed herein; for example, the melt index (I₂) can be from a lowerlimit of 0.1, 0.2, 0.5, 0.6, 0.8, 1, 1.5, 2.0, 2.5, 3.0, 3.5, 4.0, 4.5,5.0, 10, 15, 20, 30, 40, 50, 60, 80, 90, 100, or 150 g/10 minutes, to anupper limit of 0.9, 1, 1.5, 2.0, 2.5, 3.0, 3.5, 4.0, 4.5, 5.0, 10, 15,20, 30, 40, 50, 60, 80, 90, 100, 150, or 200 g/10 minutes.

In one embodiment, the ethylene-based polymers can have a melt flowratio (I₁₀/I₂) in the range of from 5 to 30. All individual values andsubranges from 5 to 30 are included herein and disclosed herein; forexample, the melt flow ratio (I₁₀/I₂) can be from a lower limit of 5,5.5, 6, 6.5, 8, 10, 12, 15, 20, or 25 to an upper limit of 5.5, 6, 6.5,8, 10, 12, 15, 20, 25, or 30.

The ethylene-based polymers may comprise less than 50 mole percent ofunits derived from one or more α-olefin comonomers. All individualvalues and subranges from less than 50 mole percent are included hereinand disclosed herein; for example, the ethylene-based polymers maycomprise from less than 30 mole percent of units derived from one ormore α-olefin comonomers; or in the alternative, less than 20 molepercent of units derived from one or more α-olefin comonomers; or in thealternative, from 1 to 20 mole percent of units derived from one or moreα-olefin comonomers; or in the alternative, from 1 to 10 mole percent ofunits derived from one or more α-olefin comonomers.

The α-olefin comonomers typically have no more than 20 carbon atoms. Forexample, the α-olefin comonomers may preferably have 3 to 10 carbonatoms, and more preferably 3 to 8 carbon atoms. Exemplary α-olefincomonomers include, but are not limited to, propylene, 1-butene,1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene, and4-methyl-1-pentene. The one or more α-olefin comonomers may, forexample, be selected from the group consisting of propylene, 1-butene,1-hexene, and 1-octene; or in the alternative, from the group consistingof 1-hexene and 1-octene.

The ethylene-based polymers may comprise greater than 50 mole percent ofunits derived from ethylene. All individual values and subranges fromgreater than 50 mole percent are included herein and disclosed herein;for example, the ethylene-based polymers may comprise at least 52 molepercent of units derived from ethylene; or in the alternative, at least65 percent by weight of units derived from ethylene; or in thealternative, at least 85 mole percent of units derived from ethylene; orin the alternative, from 50 to 100 mole percent of units derived fromethylene; or in the alternative, from 80 to 100 mole percent of unitsderived from ethylene.

In one embodiment, the ethylene-based polymer comprises an olefin blockcopolymer prepared according to an aforementioned chain-shuttlingpolymerization process. The olefin block copolymer or poly(ethylenealpha-olefin) block copolymer comprises an ethylene-derived hard segment(i.e., polyethylene hard segment) and a soft segment comprisingresiduals from the alpha-olefin and ethylene. The residuals of thealpha-olefin and ethylene typically are approximately randomlydistributed in the soft segment. Preferably, the polyethylene hardsegment is characterizable as having less than 5 mole percent (mol %) ofa residual of the alpha-olefin covalently incorporated therein.Preferably, the poly(ethylene alpha-olefin) block copolymer ischaracterizable as having a melting temperature of greater than 100° C.,and more preferably greater than 120° C., as determined by DifferentialScanning Calorimetry using the procedure described later. Thepoly(ethylene alpha-olefin) block copolymers comprise ethylene residualsand one or more copolymerizable α-olefin comonomer residuals (i.e.,ethylene and one or more copolymerizable α-olefin comonomers inpolymerized form). The poly(ethylene alpha-olefin) block copolymers arecharacterized by multiple blocks or segments of two or more polymerizedmonomer units differing in chemical or physical properties. That is, theethylene/α-olefin interpolymers are block interpolymers, preferablymulti-block interpolymers or copolymers. The terms “interpolymer” and“copolymer” are used interchangeably herein. In some embodiments, themulti-block copolymer can be represented by the following formula:(AB)_(n), where n is at least 1, preferably an integer greater than 1,such as 2, 3, 4, 5, 10, 15, 20, 30, 40, 50, 60, 70, 80, 90, 100, orhigher, “A” represents a hard block or segment and “B” represents a softblock or segment. Preferably, As and Bs are linked in a linear fashion,not in a branched or a star fashion.

“Hard” segments refer to blocks of polymerized units in which ethyleneresiduals are present in an amount greater than 95 weight percent, andpreferably greater than 98 weight percent in the poly(ethylenealpha-olefin) block copolymers. In other words, the comonomer (i.e.,alpha-olefin) residuals content in the hard segments is less than 5weight percent, and preferably less than 2 weight percent. In someembodiments, the hard segments comprise all or substantially allethylene residuals. The phrases “polyethylene hard segment” and“ethylene-derived hard segment” are synonymous and mean the hard segmentportion of a poly(ethylene alpha-olefin) block copolymer.

“Soft” segments refer to blocks of polymerized units in which thecomonomer (i.e., alpha-olefin) residuals content is greater than 5weight percent, preferably greater than 8 weight percent, greater than10 weight percent, or greater than 15 weight percent in thepoly(ethylene alpha-olefin) block copolymers. In some embodiments, thecomonomer residuals content in the soft segments can be greater than 20weight percent, greater than 25 eight percent, greater than 30 weightpercent, greater than 35 weight percent, greater than 40 weight percent,greater than 45 weight percent, greater than 50 weight percent, orgreater than 60 weight percent.

Polymerization Process

Any conventional polymerization processes may be employed to produce thepolyolefin composition according to the present invention. Suchconventional polymerization processes include, but are not limited to,solution polymerization process, particle forming polymerizationprocess, and combinations thereof using one or more conventionalreactors e.g. loop reactors, isothermal reactors, fluidized bedreactors, stirred tank reactors, batch reactors in parallel, series,and/or any combinations thereof.

In one embodiment, the polyolefin composition may be produced, forexample, via solution-phase polymerization process using one or moreloop reactors, isothermal reactors, and combinations thereof.

In general, the solution phase polymerization process occurs in one ormore well-stirred reactors such as one or more loop reactors or one ormore spherical isothermal reactors at a temperature in the range of from120° C. to 300° C.; for example, from 160° C. to 215° C., and atpressures in the range of from 300 to 1500 psi; for example, from 400 to750 psi. The residence time in solution phase polymerization process istypically in the range of from 2 to 30 minutes; for example, from 5 to15 minutes. Ethylene, one or more solvents, one or more high temperatureolefin polymerization catalyst systems, one or more co-catalysts and/orscavengers, and optionally one or more comonomers are fed continuouslyto the one or more reactors. Exemplary solvents include, but are notlimited to, isoparaffins. For example, such solvents are commerciallyavailable under the name ISOPAR E from ExxonMobil Chemical Co., Houston,Tex. The resultant mixture of the ethylene-based polymer and solvent isthen removed from the reactor and the ethylene-based polymer isisolated. Solvent is typically recovered via a solvent recovery unit,i.e. heat exchangers and vapor liquid separator drum, and is thenrecycled back into the polymerization system.

In one embodiment, the ethylene-based polymer may be produced viasolution polymerization in a single reactor system, for example a singleloop reactor system, wherein ethylene and optionally one or moreα-olefins are polymerized in the presence of one or more hightemperature olefin polymerization catalyst systems, optionally one ormore other catalysts, and optionally one or more co-catalysts. In oneembodiment, the ethylene-based polymer may be produced via solutionpolymerization in a dual reactor system, for example a dual loop reactorsystem, wherein ethylene and optionally one or more α-olefins arepolymerized in the presence of one or more an olefin polymerizationcatalyst systems, optionally one or more other catalysts, and optionallyone or more co-catalysts. In one embodiment, the ethylene-based polymermay be produced via solution polymerization in a dual reactor system,for example a dual loop reactor system, wherein ethylene and optionallyone or more α-olefins are polymerized in the presence of one or morehigh temperature olefin polymerization catalyst systems, as describedherein, in both reactors.

In one embodiment, the ethylene-based polymer may be made using a gasphase polymerization process, e.g., utilizing a fluidized bed reactor.This type reactor and means for operating the reactor are well known andcompletely described in, for example, U.S. Pat. Nos. 3,709,853;4,003,712; 4,011,382; 4,302,566; 4,543,399; 4,882,400; 5,352,749;5,541,270; EP-A-0 802 202 and Belgian Patent No. 839,380. These patentsdisclose gas phase polymerization processes wherein the polymerizationmedium is either mechanically agitated or fluidized by the continuousflow of the gaseous monomer and diluent.

A polymerization process may be effected as a continuous gas phaseprocess such as a fluid bed process. A fluid bed reactor may comprise areaction zone and a so-called velocity reduction zone. The reaction zonemay comprise a bed of growing polymer particles, formed polymerparticles and a minor amount of catalyst particles fluidized by thecontinuous flow of the gaseous monomer and diluent to remove heat ofpolymerization through the reaction zone. Optionally, some of there-circulated gases may be cooled and compressed to form liquids thatincrease the heat removal capacity of the circulating gas stream whenreadmitted to the reaction zone. A suitable rate of gas flow may bereadily determined by simple experiment. Make up of gaseous monomer tothe circulating gas stream is at a rate equal to the rate at whichparticulate polymer product and monomer associated therewith iswithdrawn from the reactor and the composition of the gas passingthrough the reactor is adjusted to maintain an essentially steady stategaseous composition within the reaction zone. The gas leaving thereaction zone is passed to the velocity reduction zone where entrainedparticles are removed. Finer entrained particles and dust may optionallybe removed in a cyclone and/or fine filter. The gas is passed through aheat exchanger wherein the heat of polymerization is removed, compressedin a compressor and then returned to the reaction zone.

The reactor temperature of the fluid bed process herein preferablyranges from 30° C. or 40° C. or 50° C. to 90° C. or 100° C. or 110° C.or 120° C. In general, the reactor temperature is operated at thehighest temperature that is feasible taking into account the sinteringtemperature of the polymer product within the reactor. In this fluid bedprocess, the polymerization temperature, or reaction temperature shouldbe below the melting or “sintering” temperature of the polymer to beformed. Thus, the upper temperature limit in one embodiment is themelting temperature of the polyolefin produced in the reactor.

A slurry polymerization process can also be used. A slurrypolymerization process generally uses pressures in the range of from 1to 50 atmospheres and even greater and temperatures in the range of 0°C. to 120° C., and more particularly from 30° C. to 100° C. In a slurrypolymerization, a suspension of solid, particulate polymer is formed ina liquid polymerization diluent medium to which ethylene and comonomersand often hydrogen along with catalyst are added. The suspensionincluding diluent is intermittently or continuously removed from thereactor where the volatile components are separated from the polymer andrecycled, optionally after a distillation, to the reactor. The liquiddiluent employed in the polymerization medium is typically an alkanehaving from 3 to 7 carbon atoms, a branched alkane in one embodiment.The medium employed should be liquid under the conditions ofpolymerization and relatively inert. When a propane medium is used theprocess must be operated above the reaction diluent critical temperatureand pressure. In one embodiment, a hexane, isopentane or isobutanemedium is employed.

Also useful is particle form polymerization, a process where thetemperature is kept below the temperature at which the polymer goes intosolution. Other slurry processes include those employing a loop reactorand those utilizing a plurality of stirred reactors in series, parallel,or combinations thereof. Non-limiting examples of slurry processesinclude continuous loop or stirred tank processes. Also, other examplesof slurry processes are described in U.S. Pat. No. 4,613,484 andMetallocene-Based Polyolefins Vol. 2 pp. 322-332 (2000), the disclosureof which are incorporated herein to the extent permitted.

In one embodiment, the catalyst composition containing at least onethiourea complex according to Formula (I) or of any embodiment of thisdisclosure may be combined with one or more additional catalysts in apolymerization process. Suitable catalysts for use include any compoundor combination of compounds that is adapted for preparing polymers ofthe desired composition or type. Both heterogeneous and homogeneouscatalysts may be employed. Examples of heterogeneous catalysts includethe well known Ziegler-Natta compositions, especially Group 4 metalhalides supported on Group 2 metal halides or mixed halides andalkoxides and the well known chromium or vanadium based catalysts.Preferably however, for ease of use and for production of narrowmolecular weight polymer segments in solution, the catalysts for useherein are homogeneous catalysts comprising a relatively pureorganometallic compound or metal complex, especially compounds orcomplexes based oil metals selected from Groups 3-10 or the Lanthanideseries of the Periodic Table of the Elements. It is preferred that anycatalyst employed herein, not significantly detrimentally affect theperformance of the other catalyst under the conditions of the presentpolymerization. Desirably, no catalyst is reduced in activity by greaterthan 25 percent, more preferably greater than 10 percent under theconditions of the present polymerization.

The ethylene-based polymers may further comprise one or more additives.Such additives include, but are not limited to, antistatic agents, colorenhancers, dyes, lubricants, pigments, primary antioxidants, secondaryantioxidants, processing aids, UV stabilizers, and combinations thereof.The ethylene-based polymers may contain any amounts of additives. Theethylene-based polymers may compromise from about 0 to about 10 percentby the combined weight of such additives, based on the weight of theethylene-based polymers and the one or more additives. Theethylene-based polymers may further compromise fillers, which mayinclude, but are not limited to, organic or inorganic fillers. Suchfillers, e.g. calcium carbonate, talc, Mg(OH)₂, may be present in levelsfrom about 0 to about 20 percent, based on the weight of the inventiveethylene-based polymers and the one or more additives and/or fillers.The ethylene-based polymers may further be blended with one or morepolymers to form a blend.

EXAMPLES

The following examples illustrate various catalyst compositionsaccording to embodiments previously described but are not intended tolimit the scope of the present disclosure in any manner.

All solvents and reagents were obtained from commercial sources and usedas received unless otherwise noted. Anhydrous toluene, hexanes,tetrahydrofuran, and diethyl ether were purified via passage throughactivated alumina and, in some cases, Q-5 reactant. Solvents used forexperiments performed in a nitrogen-filled glovebox were further driedby storage over activated 4-A molecular sieves. Glassware formoisture-sensitive reactions was dried in an oven overnight prior touse.

NMR spectra were recorded on Varian 400-MR and VNMRS-500 spectrometers.¹H NMR (proton NMR) data are reported as follows: chemical shift(multiplicity (br=broad, s=singlet, d=doublet, t=triplet, q=quartet,p=pentet, sex=sextet, sept=septet and m=multiplet), integration, andassignment). Chemical shifts for ¹H NMR data are reported in ppmdownfield from internal tetramethylsilane (TMS, 6 scale) using residualprotons in the deuterated solvent as references. ¹³C NMR (carbon NMR)data were determined with ¹H decoupling, and the chemical shifts arereported in ppm versus tetramethylsilane.

Catalyst efficiency is calculated by dividing the number of grams of thepolyolefin copolymer prepared by the total number of grams of metal M inthe catalyst used (that is, grams of metal M of the at least onemetal-ligand complex of Formula (I)). Thus, catalyst efficiency may beexpressed as grams polyolefin copolymer prepared divided by grams metalM of metal-ligand complex(es) of Formula (I) used in the polymerizationreaction.

Molecular weight data are determined by analysis on a hybrid Symyx/Dowbuilt Robot-Assisted Dilution High-Temperature Gel PermeationChromatographer (Sym-RAD-GPC). The polymer samples were dissolved byheating for 120 minutes at 160° C. in 1,2,4-trichlorobenzene (TCB) at aconcentration of 10 mg/mL stabilized by 300 ppm of butylated hydroxyltoluene (BHT). Each sample was then diluted to 1 mg/mL immediatelybefore the injection of a 250-μL aliquot of the sample. The GPC wasequipped with two Polymer Labs PLgel 10-μm MIXED-B columns (300×10 mm)at a flow rate of 2.0 mL/minute at 160° C. Sample detection wasperformed using a PolyChar IR4 detector in concentration mode. Aconventional calibration of narrow polystyrene (PS) standards wasutilized with apparent units adjusted to homo-polyethylene (PE) usingknown Mark-Houwink coefficients for PS and PE in TCB at thistemperature.

Melt temperature (T_(m)), glass transition temperature (T_(g)),crystallization temperature (T_(c)), and Heat of Melt are measured bydifferential scanning calorimetry (DSC Q2000, TA Instruments, Inc.)using a Heat-Cool-Heat temperature profile. Open-pan DSC samples of 3-6mg of polymer are first heated from room temperature to setpoint at 10°C. per minute. Traces are analyzed individually using TA UniversalAnalysis software or TA Instruments TRIOS software.

Example 1

General Ligand Synthesis Isothiocyanate Amine Ligand

  +

  →

(1a)

  +

  →

(1b)

  +

  →

(1b)

Ligands according to general structures 1a, 1b, or 1c are prepared byadding one molar equivalent of a neat amine dropwise to a solutioncontaining one molar equivalent of isothiocyanate (R¹—N═C═S, where R¹ isas defined previously in this specification) in diethyl ether (Et₂O) at25° C. A white precipitate forms instantaneously. After stirring thesolution for 30 min at 25° C., the precipitate is isolated byfiltration, washed with two aliquots of dry Et₂O, and dried undervacuum. Yields of the ligands prepared according to general structures1a, 1b, or 1c using the foregoing reaction steps are nearly quantitativewhen R¹ is 2,5-dimethylphenyl; 2,5-di(1-methylethyl)-phenyl, orcyclohexyl. Syntheses and characterization of exemplary ligands L1, L2,L3, L4, and L5, each according to one of the general structures 1a, 1b,or 1c, are described in Examples 2-6.

Example 2 Synthesis of Ligand L1

Ligand L1 was prepared according to the general method of Example 1, inwhich the group R¹ was 2,5-dimethylphenyl and the amine was pyrrolidine,in nearly quantitative yield. Ligand L1 was characterized by proton NMRand carbon-13 NMR as follows: ¹H NMR (400 MHz, CDCl₃) δ 7.11 (m, 3H),6.49 (br s, 1H), 3.69 (br s, 4H), 2.27 (s, 6H), 2.05 (br s, 4H). ¹³C NMR(101 MHz, DMSO-d₆) δ 177.59, 138.21, 136.51, 127.46, 127.46, 126.39,25.20, 18.19.

Example 3 Synthesis of Ligand L2

Ligand L2 was prepared according to the general method of Example 1, inwhich the group R¹ was 2,5-di(1-methylethyl)-phenyl and the amine waspyrrolidine, in nearly quantitative yield. Ligand L1 was characterizedby proton NMR and carbon-13 NMR as follows: ¹H NMR (400 MHz, CDCl₃) δ7.33 (t, J=7.7 Hz, 1H), 7.19 (d, J=7.7 Hz, 2H), 6.36 (br s, 1H), 3.76(br s, 4H), 3.13 (m, 2H), 2.09 (br s, 4H), 1.30 (d, J=6.8 Hz, 6H), 1.16(d, J=6.9 Hz, 6H). ¹³C NMR (101 MHz, CDCl₃) δ 179.97, 146.97, 134.06,128.78, 128.63, 125.87, 125.56, 123.67, 77.16, 28.62, 25.88, 24.38,23.08.

Example 4 Synthesis of Ligand L3

Ligand L3 was prepared according to the general method of Example 1, inwhich the group R¹ was 2,5-di(1-methylethyl)-phenyl and the amine waspiperidine, in nearly quantitative yield. Ligand L1 was characterized byproton NMR and carbon-13 NMR as follows: ¹H NMR (400 MHz, C₆D₆) δ 7.24(m, 1H), 7.15 (m, 2H), 6.26 (br s, 1H), 3.38 (m, 4H), 3.27 (m, 2H), 1.40(d, J=6.8 Hz, 6H), 1.19 (d, J=6.9 Hz, 6H), 1.15 (m, 6H). ¹³C NMR (101MHz, CDCl₃) δ 146.36, 134.48, 129.06, 128.32, 124.80, 123.62, 122.54,50.91, 49.70, 28.58, 25.74, 25.45, 24.35, 24.15, 24.08, 23.30.

Example 5 Synthesis of Ligand L4

Ligand L4 was prepared according to the general method of Example 1, inwhich the group R¹ was 2,5-di(1-methylethyl)-phenyl and the amine wasdibenzylamine (N-benzyl-1-phenylmethanamine), in nearly quantitativeyield. Ligand L1 was characterized by proton NMR and carbon-13 NMR asfollows: 1H NMR (400 MHz, C₆D₆) δ 7.21 (m, 1H), 7.10 (m, 10H), 7.03 (m,2H), 6.48 (s, 1H), 4.81 (br s, 4H), 3.09 (m, 2H), 1.45 (d, J=6.9 Hz,6H), 0.92 (d, J=6.9 Hz, 6H). ¹³C NMR (101 MHz, CDCl₃) δ 184.27, 146.44,136.22, 134.42, 129.17, 128.40, 128.10, 126.94, 123.52, 54.93, 28.68,24.20, 23.07.

Example 6 Synthesis of Ligand L5

Ligand L5 was prepared according to the general method of Example 1, inwhich the group R¹ was cyclohexyl and the amine was pyrrolidine, innearly quantitative yield. Ligand L1 was characterized by proton NMR andcarbon-13 NMR as follows: 1H NMR (400 MHz, C₆D₆) δ 4.70 (m, 1H), 4.56(d, J=6.9 Hz, 1H), 3.09 (br s, 4H), 2.19 (m, 2H), 1.56 (dt, J=13.5, 3.6Hz, 2H), 1.45 (dt, J=12.8, 3.7 Hz, 1H), 1.28 (m, 2H), 1.18 (m, 4H), 1.01(m, 3H). ¹³C NMR (101 MHz, DMSO-d₆) δ 176.89, 53.61, 49.46, 32.26,25.28, 25.16, 24.81.

Example 7 Synthesis and Characterization of Catalyst C1

Catalyst C1 was prepared by dissolving in 5 mL of dichloromethane(CH₂Cl₂) two molar equivalents of thiourea ligand L1 (0.100 g, 0.43mmol) prepared according to Example 2 of this specification and thenmixing resulting solution with one molar equivalent oftetrabenzylzirconium (ZrBn₄) (0.097 g, 0.21 mmol). After 10 min thesolvent was removed under vacuum. The solids were further dried underhigh vacuum overnight to afford the product (catalyst C1) inquantitative yield.

Catalyst C1 was characterized by proton NMR and carbon-13 NMR asfollows: ¹H NMR (400 MHz, C₆D₆) δ 7.39 (dd, J=8.3, 1.1 Hz, 4H), 7.21 (t,J=7.7 Hz, 4H), 6.89 (tt, J=7.2, 1.2 Hz, 2H), 6.78 (s, 6H), 3.42 (br s,4H), 2.85 (s, 4H), 2.31 (br s, 4H), 2.13 (s, 12H), 0.86 (br s, 8H). ¹³CNMR (101 MHz, C₆D₆) δ 174.19, 149.22, 146.77, 133.57, 125.21, 121.47,80.84, 20.11.

Example 8 Synthesis and Characterization of Catalyst C2

Catalyst C2 was prepared by dissolving in 5 mL of CH₂Cl₂ two molarequivalents of thiourea ligand L2 (0.100 g, 0.34 mmol) preparedaccording to Example 3 of this specification and then mixing theresulting solution with one molar equivalent of ZrBn₄ (0.078 g, 0.17mmol). After 10 min the solvent was removed under vacuum. The solidswere further dried under high vacuum overnight to afford the product(catalyst C2) in quantitative yield.

Catalyst C2 was characterized by proton NMR and carbon-13 NMR asfollows: ¹H NMR (400 MHz, C₆D₆) δ 7.36 (d, J=7.1 Hz, 4H), 7.22 (t, J=7.7Hz, 4H), 7.05 (m, 6H), 6.88 (t, J=7.3 Hz, 2H), 3.50 (dt, J=13.4, 6.7 Hz,4H), 3.41 (br s, 4H), 2.61 (s, 4H), 2.51 (br s, 4H), 1.34 (d, J=6.8 Hz,12H), 1.19 (d, J=6.8 Hz, 12H), 0.90 (m, 8H). ¹³C NMR (101 MHz, C₆D₆) δ173.86, 149.34, 144.87, 144.63, 127.99, 126.98, 121.49, 85.58, 29.44,25.73, 24.63, 21.77.

Example 9 Synthesis and Characterization of Catalyst C3

Catalyst C3 was prepared by dissolving in 5 mL of CH₂Cl₂ two molarequivalents of thiourea ligand L5 (0.100 g, 0.47 mmol) preparedaccording to Example 6 of this specification and then mixing theresulting solution with one molar equivalent of ZrBn₄ (0.107 g, 0.24mmol). After 10 min the solvent was removed under vacuum. The solidswere further dried under high vacuum overnight to afford the product(catalyst C₃) in quantitative yield.

Catalyst C3 was characterized by proton NMR and carbon-13 NMR asfollows: ¹H NMR (400 MHz, C₆D₆) δ 7.34 (d, J=7.1 Hz, 4H), 7.14 (m, 4H),6.83 (t, J=7.3 Hz, 2H), 3.35 (m, 8H), 3.25 (s, 4H), 1.81 (d, J=12.2 Hz,4H), 1.54 (m, 11H), 1.23 (s, 9H), 1.06 (m, 6H). ¹³C NMR (101 MHz, C₆D₆)δ 177.18, 151.28, 128.27, 127.37, 120.67, 74.64, 58.06, 51.56, 26.46,26.17, 25.72.

Example 10 Synthesis and Characterization of Catalyst C4

Catalyst C4 was prepared by dissolving in 5 mL of CH₂Cl₂ two molarequivalents of thiourea ligand L5 (0.041 g, 0.19 mmol) preparedaccording to Example 6 of this specification and mixing the resultingsolution was mixed with tetrabenzylhafnium (HfBn₄) (0.052 g, 0.10 mmol).After 10 min the solvent was removed under vacuum. The solids werefurther dried under high vacuum overnight to afford the product(catalyst C4) in quantitative yield.

Catalyst C4 was characterized by proton NMR and carbon-13 NMR asfollows: ¹H NMR (400 MHz, C₆D₆) δ 7.32 (d, J=7.1 Hz, 4H), 7.18 (m, 4H),6.79 (t, J=7.3 Hz, 2H), 3.32 (br s, 8H), 2.87 (br s, 2H), 2.78 (br s,2H), 1.83 (d, J=11.5 Hz, 4H), 1.55 (m, 11H), 1.19 (br s, 9H), 1.06 (brs, 6H). ¹³C NMR (101 MHz, C₆D₆) δ 175.54, 152.01, 129.67, 128.02,127.50, 126.03, 120.69, 79.45, 57.77, 51.61, 35.29, 34.32, 26.44, 26.19,25.68.

Example 11 Synthesis and Characterization of Catalyst C5

Catalyst C5 was prepared by dissolving in 5 mL of CH₂Cl₂ one molarequivalent of thiourea ligand L1 (0.050 g, 0.21 mmol) prepared accordingto Example 2 of this specification and mixing the resulting solutionwith one molar equivalent of ZrBn₄ (0.097 g, 0.21 mmol). After 10 minthe solvent was removed under vacuum (0.129 g). The product wasdissolved in 5 mL of toluene and layered with 10 mL pentane. The vialthen was cooled to −30° C. overnight. The resulting cloudy solution waspassed through a 0.45-μm syringe filter, and the filtrate was evaporatedto dryness under vacuum. The total yield of catalyst C5 was 0.115 g(90%).

Catalyst C5 was characterized by proton NMR and carbon-13 NMR asfollows: ¹H NMR (400 MHz, C₆D₆) δ 7.15 (m, 6H), 6.96 (t, J=7.4 Hz, 3H),6.91 (m, 6H), 6.85 (s, 3H), 3.38 (s, 2H), 2.27 (s, 2H), 2.11 (s, 6H),2.05 (s, 6H), 0.84 (s, 4H). ¹³C NMR (101 MHz, C₆D₆) δ 172.87, 147.46,142.71, 134.14, 131.30, 130.18, 129.77, 126.12, 123.77, 76.69, 19.56.

Example 12 Synthesis and Characterization of Catalyst C6

Catalyst C6 was prepared by dissolving in 5 mL of CH₂Cl₂ one molarequivalent of thiourea ligand L2 (0.050 g, 0.17 mmol) prepared accordingto Example 3 of this specification and mixing the resulting solutionwith one molar equivalent of ZrBn₄ (0.078 g, 0.17 mmol). After 10 minthe solvent was removed under vacuum (0.112 g). The product wasdissolved in 5 mL of toluene and layered with 10 mL pentane. The vialwas cooled to −30° C. overnight. The resulting cloudy solution waspassed through a 0.45-μm syringe filter, and the filtrate was evaporatedto dryness under vacuum. The total yield of catalyst C6 was 0.110 g(89%).

Catalyst C₆ was characterized by proton NMR and carbon-13 NMR asfollows: ¹H NMR (400 MHz, C₆D₆) δ 7.15 (m, 6H), 7.02 (m, 3H), 6.96 (m,9H), 3.44 (s, 2H), 3.27 (p, J=6.8 Hz, 2H), 2.50 (s, 2H), 2.18 (s, 6H),1.24 (d, J=6.8 Hz, 6H), 1.10 (d, J=6.8 Hz, 6H), 0.89 (m, 4H). ¹³C NMR(101 MHz, C₆D₆) δ 173.00, 131.30, 130.04, 130.00, 129.07, 127.22,124.12, 123.84, 77.24, 29.54, 24.82, 24.20.

Example 13 Synthesis and Characterization of Catalyst C7

Catalyst C7 was prepared by dissolving in 5 mL of CH₂Cl₂ one molarequivalent of thiourea ligand L3 (0.050 g, 0.16 mmol) prepared accordingto Example 4 of this specification and mixing the resulting solutionwith one molar equivalent of ZrBn₄ (0.075 g, 0.16 mmol). After 10 minthe solvent was removed under vacuum. The solids were further driedunder high vacuum overnight to afford the product (catalyst C7) inquantitative yield.

Catalyst C7 was characterized by proton NMR and carbon-13 NMR asfollows: ¹H NMR (400 MHz, C₆D₆) δ 7.14 (m, 6H), 7.06 (s, 3H), 6.94 (m,9H), 3.15 (p, J=6.8 Hz, 2H), 3.01 (br s, 4H), 2.15 (s, 6H), 1.24 (d,J=6.8 Hz, 6H), 1.09 (d, J=6.8 Hz, 6H), 1.02 (m, 4H), 0.96 (m, 2H). ¹³CNMR (101 MHz, C₆D₆) δ 175.65, 145.69, 142.85, 142.58, 130.01, 129.96,126.92, 124.89, 123.85, 77.40, 49.78, 29.31, 26.64, 24.97, 24.81, 24.36.

Example 14 Synthesis and Characterization of Catalyst C8

Catalyst C8 was prepared by dissolving in 5 mL of CH₂Cl₂ one molarequivalent of thiourea ligand L4 (0.050 g, 0.12 mmol) and mixing theresulting solution with one molar equivalent of ZrBn₄ (0.055 g, 0.12mmol). After 10 min the solvent was removed under vacuum. The solidswere further dried under high vacuum overnight to afford the product(catalyst C₈) in quantitative yield.

Catalyst C₈ was characterized by proton NMR and carbon-13 NMR asfollows: ¹H NMR (400 MHz, C₆D₆) δ 7.19 (t, J=7.7 Hz, 6H), 6.99 (m, 22H),4.29 (br s, 4H), 3.15 (p, J=6.7 Hz, 2H), 2.21 (s, 6H), 1.23 (d, J=6.7Hz, 6H), 0.70 (d, J=6.7 Hz, 6H). ¹³C NMR (101 MHz, C₆D₆) δ 176.66,144.97, 143.16, 142.47, 136.23, 130.22, 130.02, 129.30, 127.09, 124.98,124.00, 78.24, 29.20, 25.59, 24.85.

Example 15 Synthesis and Characterization of Catalyst C9

Catalyst C9 was prepared by dissolving in 5 mL of CH₂Cl₂ one molarequivalent of thiourea ligand L1 (0.050 g, 0.21 mmol) prepared accordingto Example 2 of this specification and mixing the resulting solutionwith one molar equivalent of HfBn₄ (0.116 g, 0.21 mmol). After 10 minthe solvent was removed under vacuum and the product was dissolved in 5mL of toluene, then mixed with 15 mL of hexane. The vial was cooled to−30° C. overnight. A large amount of solids formed. The solid materialwas isolated by filtration and dried under vacuum. The total yield ofcatalyst C₉ was 0.121 g (83%).

Catalyst C₉ was characterized by proton NMR and carbon-13 NMR asfollows: ¹H NMR (400 MHz, C₆D₆) δ 7.18 (t, J=7.7 Hz, 6H), 7.00 (d, J=7.3Hz, 6H), 6.94 (t, J=7.3 Hz, 3H), 6.83 (m, 3H), 3.33 (br s, 2H), 2.26 (brs, 2H), 2.04 (s, 6H), 1.94 (s, 6H), 0.80 (br s, 4H). ¹³C NMR (101 MHz,C₆D₆) δ 170.87, 146.43, 142.90, 134.48, 134.41, 129.81, 129.65, 126.54,123.68, 84.68, 19.84, 19.34.

Example 16 Synthesis and Characterization of Catalyst C10

Catalyst C10 was prepared by dissolving in 5 mL of CH₂Cl₂ one molarequivalent of thiourea ligand L2 (0.050 g, 0.17 mmol) prepared accordingto Example 3 of this specification and mixing the resulting solutionwith one molar equivalent of HfBn₄ (0.093 g, 0.17 mmol). After 10 minthe solvent was removed under vacuum. The product was dissolved in 5 mLof toluene and mixed with 15 mL of hexane. The vial then was cooled to−30° C. overnight. The resulting cloudy solution was passed through a0.45-μm syringe filter, and the filtrate was evaporated to dryness undervacuum. The total yield of catalyst C10 was 0.122 g (96%).

Catalyst C10 was characterized by proton NMR and carbon-13 NMR asfollows: 1H NMR (400 MHz, C₆D₆) δ 7.18 (t, J=7.7 Hz, 6H), 7.05 (d, J=7.2Hz, 7H), 7.00 (s, 1H), 6.98 (d, J=1.8 Hz, 1H), 6.94 (t, J=7.3 Hz, 3H),3.40 (br s, 2H), 3.18 (p, J=6.8 Hz, 2H), 2.42 (br s, 2H), 2.00 (s, 6H),1.23 (d, J=6.8 Hz, 6H), 1.04 (d, J=6.8 Hz, 6H), 0.84 (br s, 4H). ¹³C NMR(101 MHz, C₆D₆) δ 171.38, 144.36, 143.89, 143.05, 129.83, 129.58,127.68, 124.09, 123.68, 85.48, 29.61, 24.84, 24.15.

Example 17 Synthesis and Characterization of Catalyst C11

Catalyst C11 was prepared by dissolving in 5 mL of CH₂Cl₂ one molarequivalent of thiourea ligand L3 (0.050 g, 0.16 mmol) prepared accordingto Example 4 of this specification and mixing the resulting solutionwith one molar equivalent of HfBn₄ (0.089 g, 0.16 mmol). After 10 minthe solvent was removed under vacuum. The product was dissolved in 5 mLof toluene and mixed with 15 mL of hexane. The vial then was cooled to−30° C. overnight. The resulting slightly cloudy solution was passedthrough a 0.45-μm syringe filter, and the filtrate was evaporated todryness under vacuum. The total yield of catalyst C11 was 0.121 g (98%).

Catalyst C11 was characterized by proton NMR and carbon-13 NMR asfollows: ¹H NMR (400 MHz, C₆D₆) δ 7.17 (t, J=7.7 Hz, 6H), 7.03 (s, 6H),7.01 (s, 3H), 6.93 (t, J=7.3 Hz, 3H), 3.08 (p, J=6.8 Hz, 2H), 2.95 (brs, 4H), 1.99 (s, 6H), 1.24 (d, J=6.8 Hz, 6H), 1.03 (d, J=6.8 Hz, 6H),0.98 (m, 4H), 0.92 (m, 2H). ¹³C NMR (101 MHz, C₆D₆) δ 174.13, 144.41,143.12, 129.79, 129.52, 127.38, 124.86, 123.67, 85.98, 50.02, 29.37,26.53, 25.01, 24.72, 24.26.

Example 18 Synthesis and Characterization of Catalyst C12

Catalyst C12 was prepared by dissolving in 5 mL of CH₂Cl₂ one molarequivalent of thiourea ligand L4 (0.060 g, 0.14 mmol) prepared accordingto Example 5 of this specification and mixing the resulting solutionwith one molar equivalent of HfBn₄ (0.078 g, 0.14 mmol). After 10 minthe solvent was removed under vacuum. The product was dissolved in 5 mLof toluene and mixed with 15 mL of hexane. The vial then was cooled to−30° C. overnight. The resulting slightly cloudy solution was passedthrough a 0.45-μm syringe filter, and the filtrate was evaporated todryness under vacuum. The total yield of catalyst C₁₂ was 0.123 g (99%).

Catalyst C₁₂ was characterized by proton NMR and carbon-13 NMR asfollows: ¹H NMR (400 MHz, C₆D₆) δ 7.22 (t, J=7.7 Hz, 6H), 6.99 (m, 22H),4.69 (br s, 2H), 4.09 (br s, 2H), 3.07 (p, J=6.7 Hz, 2H), 2.05 (s, 6H),1.23 (d, J=6.7 Hz, 6H), 0.65 (d, J=6.7 Hz, 6H). ¹³C NMR (101 MHz, C₆D₆)δ 175.50, 143.70, 143.41, 143.08, 135.89, 129.96, 129.67, 129.54,129.35, 127.56, 126.04, 124.97, 123.78, 87.12, 29.28, 25.67, 24.74.

Example 19 Batch Copolymerization of Ethylene and 1-Octene

To determine the effectiveness of various catalysts according toembodiments of this specification, ethylene and 1-octene were batchcopolymerized in the presence of catalysts C1, C2, C3, C5, C6, C7, andC8.

The copolymerizations were conducted in a 1 G Autoclave batch reactordesigned for ethylene homopolymerizations and ethylene/α-olefincopolymerizations. The reactor was heated by electrical heating bandsand cooled by an internal serpentine cooling coil containing chilledglycol. Both the reactor and the heating/cooling system were controlledand monitored by a Camile TG process computer. The bottom of the reactorwas fitted with a dump valve that emptied the reactor contents into aglass dump pot for runs that were saved or to a plastic dump drum forwaste. The dump pot was vented to the atmosphere with both the drum andglass kettle under a nitrogen purge. All chemicals used forpolymerization or catalyst makeup (including solvents and monomers) wererun through purification columns to remove any impurities that couldaffect the polymerization. High-pressure nitrogen and high-pressurehydrogen were ultra-high purity grade, supplied by Airgas.

The reactor was charged with Isopar E and 1-octene via independentMicromotion Flow Meters. The reactor was heated to the polymerizationsetpoint. Ethylene was added to the reactor at the reaction temperatureto maintain the reaction pressure setpoint. Ethylene addition amountswere monitored by a Micromotion Flow Meter.

An MMAO-3A scavenger, an RIBS-II activator ([HNMe(C₁₈H₃₇)₂][B(C₆F₅)₄]),and a catalyst (one of catalysts C1, C2, C3, C5, C6, C7, or C8) weremixed with an appropriate amount of toluene in an inert-atmosphere glovebox to achieve a desired molarity solution. The mixture was drawn into asyringe and transferred into the catalyst shot tank located outside theglove box. The mixture was added via high-pressure N₂ injection when thereactor pressure setpoint was achieved.

Immediately after catalyst addition, the run timer was started. Usuallywithin the first minute of successful catalyst runs, an exotherm wasobserved, as well as decreasing reactor pressure. Then, ethylene wasadded by the Camile utilizing a Bronkhorst pressure controller tomaintain the pressure setpoint in the reactor. The polymerizations wererun for up to 10 minutes (or less than 10 minutes if a target ethyleneuptake was observed), then the agitator was stopped and the bottom dumpvalve was opened to empty the reactor contents to the kettle. The kettlecontents were poured into trays and placed in a lab hood, where thesolvent was evaporated off overnight. The trays containing the remainingpolymer were then transferred to a vacuum oven, where they were heatedat 100° C. under vacuum to remove any remaining solvent. After the trayscooled to ambient temperature, the polymers were weighed for yields andefficiencies and were submitted for polymer testing.

Two runs of 10 minutes, one at 120° C. and another at 150° C., wereconducted for each of the catalysts C1, C2, C3, C5, C6, C7, and C8.Pertinent data for each of the runs are provided in Table 1.

TABLE 1 Batch Polymerizations of Ethylene and 1-Octene Using ExemplaryCatalysts Catalyst Efficiency Octene Octene Temp Loading Poly (kg poly/M_(w) Content Content T_(m) ΔH_(m) Catalyst (° C.) (μmol) (g) g metal)(kg/mol) PDI (wt %) (mol %) (° C.)* (J/g)* C1 120 2.00 8 44 101 4.7 15.14.3 113 132 150 4.50 12 29 43 3.9 18.4 5.3 117 112 C2 120 3.00 3 11 15115.7 21.1 6.3 117 116 150 Inactive C3 120 4.00 6 16 214 8.0 16.3 4.6 100119 150 15.00 7 5 227 14.1 12.4 3.4 94 111 C5 120 2.50 32 140 102 4.919.9 5.8 113 115 150 5.00 20 44 49 3.5 22.8 6.9 79 97 C6 120 2.50 28 12396 4.8 15.9 4.5 115 119 150 4.25 23 59 46 3.7 18.1 5.2 112 113 C7 1202.50 30 132 97 5.2 15.9 4.5 114 115 150 4.00 21 58 44 3.7 19.0 5.5 111118 C8 120 2.50 16 70 66 3.9 16.3 4.6 113 124 150 4.50 12 29 45 23.617.3 5.0 114 144 *DSC data pertaining to T_(m) and ΔH_(m) are given forthe second heat cycle Polymerization conditions: Activator[HNMe(C₁₈H₃₇)₂][B(C₆F₅)₄] (1.2 equiv); MMAO-3A (10 equiv). Runs atTemperature = 120° C.: 1180 g of Isopar E; 570 g of 1-octene; no H₂; 280psi of ethylene; 10 min run time. Runs at Temperature = 150° C.: 1045 gof Isopar E; 570 g of 1-octene; no H₂; 317 psi of ethylene; 10 min runtime.

It should be apparent to those skilled in the art that variousmodifications and variations can be made to the embodiments describedherein without departing from the spirit and scope of the claimedsubject matter. Thus it is intended that the specification cover themodifications and variations of the various embodiments described hereinprovided such modification and variations come within the scope of theappended claims and their equivalents.

1. A composition comprising at least one thiourea complex according toFormula (I):MQ_(a)X_(4-a)  (I) where: M is a metal center chosen from Ti, Zr, or Hf;a is 1 or 2; each group Q of the at least one thiourea complex is abidentate thiourea ligand bound to the metal center, the thiourea ligandhaving Formula (Ia), Formula (Ib), or Formula (Ic):

each group R¹, R², and R³ in the at least one thiourea complex isindependently chosen from alkyl groups or aryl groups; each group Z¹ andZ² in the at least one thiourea complex is a divalent alkylene group; ifa=2, groups R¹ of the two groups Q are optionally linked to each otherthrough at least one covalent bond, or groups R³ of the two groups Q areoptionally linked to each other through at least one covalent bond; andeach X is covalently bonded or coordinated to the metal center and isindependently chosen from alkyl groups, halides, or amides.
 2. Thecomposition of claim 1, wherein: a is 1; and the at least one thioureacomplex has Formula (IIa), Formula (IIb), or Formula (IIc):

where M, R¹, R², R³, Z¹, Z², and X are as defined in Formula (I).
 3. Thecomposition of claim 2, wherein R¹ is a substituted phenyl group or acycloalkyl group.
 4. The composition of claim 2, wherein each R¹ is

where A¹ and A² are independently a (C₁-C₁₀) alkyl group.
 5. (canceled)6. The composition of claim 4, wherein A¹ and A² are independentlychosen from methyl; ethyl; propyl; 1-methylethyl; 1,1-dimethylethyl; orbutyl. 7-8. (canceled)
 9. The composition of claim 2, wherein the atleast one thiourea complex has Formula (IIa), where R² and R³ areindependently —(CH₂)_(n)Ph groups, where n is from 0 to
 5. 10-11.(canceled)
 12. The composition of claim 2, wherein the at least onethiourea complex has Formula (IIc), where Z² is a C₄ to C₁₀ alkylenegroup. 13-19. (canceled)
 20. The composition of claim 2, wherein the atleast one thiourea complex is chosen from compounds C5, C6, C7, C8, C9,C10, C11, C12, or combinations thereof:


21. The composition of claim 1, wherein: a is 2; and the at least onethiourea complex has Formula (IIIa), Formula (IIIb), Formula (IIIc),Formula (IIId), Formula (Ille), or Formula (IIIf):

where M, R¹, R², R³, Z¹, Z², and X are as defined in Formula (I). 22.The composition of claim 21, wherein the at least one thiourea complexhas Formula (IIId), Formula (IIIe), or Formula (IIIf); and Z² is a(C₄-C₁₀)alkylene group.
 23. The composition of claim 22, wherein Z² is a(C₄-C₅) alkylene group. 24-25. (canceled)
 26. The composition of claim22, wherein: Z² is —(CH₂)₄— or —(CH₂)₅—; and R¹ is cyclohexyl or

where A¹ and A² are independently a (C₁-C₁₀) alkyl group. 27-31.(canceled)
 32. The composition of claim 21, wherein the at least onethiourea complex is chosen from compounds C1, C2, C3, C4, orcombinations thereof:


33. The composition of claim 1, wherein: a is 2; groups R¹ of the twogroups Q are linked to each other as a bridging group Z³; and the atleast one thiourea complex has Formula (IVa), Formula (IVb), or Formula(IVc):

where: M, R¹, R², R³, Z¹, Z², and X are as defined in Formula (I); andZ³ is an alkylene group.
 34. The composition of claim 33, wherein Z³ isa (C₃-C₄₀) alkylene group. 35-37. (canceled)
 38. The composition ofclaim 1, wherein: a is 2; groups R³ of the two groups Q are linked toeach other as a bridging group Z⁴; and the at least one thiourea complexhas Formula (Va), Formula (Vb), or Formula (Vc):

where: M, R¹, R², Z¹, and X are as defined in Formula (I); and Z⁴ is analkylene group.
 39. The composition of claim 38, wherein Z⁴ is a(C₃-C₄₀) alkylene group. 40-46. (canceled)
 47. A polymerization methodcomprising: reacting ethylene and an α-olefin comonomer in the presenceof a catalytic amount of the composition of claim 1 to form anethylene-co-alkylene copolymer, wherein the α-olefin comonomer comprisesat least one C₃-C₁₂ α-olefin.
 48. The polymerization catalyst system ofclaim 47, wherein the composition comprises at least one thioureacomplex chosen from compounds of Formula C1, C2, C3, C4, C5, C6, C7, orcombinations thereof:


49. The polymerization method of claim 47, wherein the α-olefincomonomer is 1-octene.